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TABLE OF CONTENTS

Table of Contents

Filed pursuant to Rule 424(b)(3)
SEC File No. 333-166797

The information in this preliminary prospectus supplement relates to an effective registration statement under the Securities Act of 1933 but is not complete and may be changed. This preliminary prospectus supplement and the accompanying base prospectus are not an offer to sell these securities, and we are not soliciting an offer to buy these securities, in any state where the offer or sale is not permitted.

6,200,000 Common Units

Representing Limited Partner Interests

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We are selling 6,200,000 common units representing limited partner interests in NuStar Energy L.P., including approximately 490,000 common units to William E. Greehey, the Chairman of the board of directors of NuStar GP, LLC.

Our common units are listed on the New York Stock Exchange, or NYSE, under the symbol "NS." The last reported sales price of our common units on the New York Stock Exchange on August 31, 2012 was $50.72 per common unit.

Investing in our common units involves risks. Please read "Risk Factors" beginning on page S-10 of this prospectus supplement and page 4 of the accompanying base prospectus for information regarding risks you should consider before investing in our common units.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus supplement or the accompanying base prospectus. Any representation to the contrary is a criminal offense.

We have granted the underwriters a 30-day option to purchase up to an additional 930,000 common units from us on the same terms and conditions as set forth above if the underwriters sell more than 6,200,000 common units in this offering.

The underwriters are offering the common units as set forth in "Underwriting (Conflicts of Interest)." Delivery of the common units will be made on or about September              , 2012.

Joint Book-Running Managers

 

Co-Managers

   

September              , 2012

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This map depicts our operations as of August 31, 2012.

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This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of this offering of common units. The second part is the accompanying base prospectus, which gives more general information, some of which may not apply to this offering of common units. Generally, when we refer only to the "prospectus," we are referring to both parts combined. If the information about the common unit offering varies between this prospectus supplement and the accompanying base prospectus, you should rely on the information in this prospectus supplement.

We have not authorized anyone to provide any information or to make any representations other than those contained or incorporated by reference in this prospectus or in any free writing prospectuses we have prepared. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. This prospectus is not an offer to sell the common units offered hereby under circumstances and in jurisdictions where it is unlawful to do so. The information contained in this prospectus and in the documents incorporated by reference herein is current only as of the respective dates of such documents. Our business, financial condition, results of operations and prospects may have changed since those dates.

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Prospectus Supplement

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Risk factors

Limited partner interests are inherently different from the capital stock of a corporation, although many of the business risks to which we are subject are similar to those that would be faced by a corporation engaged in a similar business. Before you invest in our securities, you should carefully consider those risk factors set forth below and those included in our Annual Report on Form 10-K for the year ended December 31, 2011 that are incorporated herein by reference, together with all of the other information included in this prospectus supplement, the accompanying base prospectus and the documents incorporated herein by reference, in evaluating an investment in our common units.

If any of the risks discussed below or in the foregoing documents were actually to occur, our business, financial condition, results of operations or cash flow could be materially adversely affected. In that case, our ability to make distributions to our unitholders may be reduced, the trading price of our common units could decline and you could lose all or part of your investment.

Failure to successfully complete the transactions related to the Asphalt JV in the expected time frame may adversely affect our future results, which may adversely affect the value of our common units.

Failure to successfully complete the transactions related to Asphalt JV within the expected timeframe in the third quarter of 2012 may prevent us from achieving the anticipated benefits of entering into the Asphalt JV. To realize these anticipated benefits, we and Lindsay Goldberg must successfully complete the joint venture, including the related credit facilities, and transition the Asphalt Operations into the new joint venture. We may not be able to realize the anticipated benefits to us of the joint venture or such benefits may take longer to realize than expected. In addition, the actual transition may result in additional and unforeseen expenses and liabilities, which could reduce the anticipated benefits of the joint venture and adversely affect our results of operations.

Our partner in the Asphalt JV, as well as partners in any future joint ventures into which we may enter, may have obligations that are important to the success of the joint venture, such as the obligation to pay their share of capital and other costs of the joint venture. The performance of these third party obligations, including the ability of the third parties to satisfy their obligations under these arrangements, is outside our control. In addition, we may incur liabilities as a result of an action taken by our joint venture partners and disputes between us and our joint venture partners may result in delays, litigation or operational impasses. Such failures, actions or disputes may have an adverse affect on our business and results of operations.

Our future financial and operating flexibility may be adversely affected by our significant leverage, downgrades of our credit ratings, our significant working capital needs, restrictions in our debt agreements and disruptions in the financial markets.

As of June 30, 2012, our consolidated debt was $2.6 billion. Among other things, our significant leverage may be viewed negatively by credit rating agencies, which could result in increased costs for us to access the capital markets. NuStar Logistics and NuPOP have senior unsecured ratings of Baa3 with Moody's Investor Service, Inc. (Moody's), which rating is under review, and were recently downgraded to BB+ by Standard & Poor's Ratings Services (S&P) and Fitch, Inc. (Fitch). Moody's, S&P and Fitch have assigned NuStar Logistics and NuPOP a stable outlook. As a result of S&P's downgrade of our credit rating, the interest rate on the $350.0 million of 7.65% senior notes due 2018 increased by 0.25%. Any further ratings downgrade by Moody's on the debt issued by NuStar Logistics could result in an increase of the interest rates on the senior notes due 2018 and under our revolving credit agreement. Any further downgrades may require us to post cash collateral under

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certain of our hedging arrangements, which we would fund with borrowings under the revolving credit facility. Future downgrades of our debt could significantly increase our capital costs and adversely affect our ability to raise capital in the future.

We require significant amounts of working capital to make purchases of crude oil and maintain necessary seasonal inventories to support our refining operations. After the closing of the transfer of the Asphalt Operations to Asphalt JV, NuStar Logistics will provide an unsecured credit facility to Asphalt JV to fund working capital loans to Asphalt JV in an aggregate principal amount not to exceed $250 million and NuStar Energy has agreed to provide guarantees or credit support, as applicable, of up to $150 million under operating contracts related to the Asphalt Operations. We believe that our current sources of capital are adequate to meet our working capital needs. However, if our working capital needs increase more than anticipated, we may be forced to seek additional sources of capital, which may not be available or available on commercially reasonable terms.

The agreement governing our five-year revolving credit facility, as amended (the Revolving Credit Agreement) contains restrictive covenants, including a requirement that we maintain, as of the last day of the fiscal quarter ending September 30, 2012, a consolidated debt coverage ratio not to exceed 6.00 to 1.00, and, for subsequent fiscal quarters, a consolidated debt coverage ratio not to exceed 5.00 to 1.00; provided, that for the rolling period ending on June 30 of each year (commencing with the rolling period ending June 30, 2013), NuStar Energy's consolidated debt coverage ratio may not exceed 5.50 to 1.00 for such rolling period. Notwithstanding the foregoing (but subject to the following sentence), if all or substantially all of NuStar Energy's asphalt assets and operations are owned by an unconsolidated joint venture, then the consolidated debt coverage ratio shall not exceed 5.00 to 1.00 for such fiscal quarters. If at any time NuStar Energy has consummated one or more acquisitions within the two most recently completed fiscal quarters for an aggregate of at least $50.0 million, then, for the two rolling periods the last day of which immediately follows the date on which such acquisition is consummated, the numerator of the maximum consolidated debt coverage ratio otherwise permitted above shall be increased by 0.50 (not to exceed 5.50 to 1.00 for such rolling periods). Failure to comply with any of the restrictive covenants in the Revolving Credit Agreement will result in a default under the terms of our credit agreement and could result in acceleration of this and possibly other indebtedness.

Debt service obligations, restrictive covenants in our credit facilities and the indentures governing our outstanding senior notes and maturities resulting from this leverage may adversely affect our ability to finance future operations, pursue acquisitions, fund other capital needs and our ability to pay cash distributions to our unitholders. In addition, this leverage may make our results of operations more susceptible to adverse economic or operating conditions. For example, during an event of default under any of our debt agreements, we would be prohibited from making cash distributions to our unitholders. If our lenders file for bankruptcy or experience severe financial hardship, they may not honor their pro rata share of our borrowing requests under the Revolving Credit Agreement, which may significantly reduce our available borrowing capacity and, as a result, materially adversely affect our financial condition and ability to pay distributions to our unitholders.

Additionally, we may not be able to access the capital markets in the future at economically attractive terms, which may adversely affect our future financial and operating flexibility and our ability to pay cash distributions at current levels.

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Risk factors

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The tax treatment of publicly traded partnerships or an investment in our common units could be subject to potential legislative, judicial or administrative changes and differing interpretations, possibly on a retroactive basis.

The present U.S. federal income tax treatment of publicly traded partnerships, including us, or an investment in our common units may be modified by administrative, legislative or judicial interpretation at any time. For example, from time to time, members of Congress propose and consider substantive changes to the existing federal income tax laws that affect publicly traded partnerships. Currently, one such legislative proposal would eliminate the qualifying income exception upon which we rely for our treatment as a partnership for U.S. federal income tax purposes. We are unable to predict whether any of these changes, or other proposals, will ultimately be enacted. However, it is possible that a change in law could affect us and may be applied retroactively. Any such changes could negatively impact the value of an investment in our common units.

We prorate our items of income, gain, loss and deduction between transferors and transferees of our common units each month based upon the ownership of our common units on the first day of each month, instead of on the basis of the date a particular unit is transferred. The IRS may challenge this treatment, which could change the allocation of items of income, gain, loss and deduction among our unitholders.

We prorate our items of income, gain, loss and deduction between transferors and transferees of our common units each month based upon the ownership of our common units on the first day of each month, instead of on the basis of the date a particular unit is transferred. The use of this proration method may not be permitted under existing Treasury Regulations, and, accordingly, our counsel is unable to opine as to the validity of this method. If the IRS were to challenge this method or new Treasury Regulations were issued, we may be required to change the allocation of items of income, gain, loss and deduction among our unitholders.

A unitholder whose common units are loaned to a short seller to cover a short sale of common units may be considered as having disposed of those common units. If so, he would no longer be treated for tax purposes as a partner with respect to those common units during the period of the loan and may recognize gain or loss from the disposition.

Because there is no tax concept of loaning a partnership interest, a unitholder whose common units are loaned to a short seller to cover a short sale of common units may be considered as having disposed of the loaned units. The unitholder may no longer be treated for tax purposes as a partner with respect to those common units during the period of the loan to the short seller and the unitholder may recognize gain or loss from such disposition. Moreover, during the period of the loan to the short seller, any of our income, gain, loss or deduction with respect to those common units may not be reportable by the unitholder and any cash distributions received by the unitholder as to those common units could be fully taxable as ordinary income. Unitholders desiring to assure their status as partners and avoid the risk of gain recognition from a loan to a short seller should modify any applicable brokerage account agreements to prohibit their brokers from borrowing their common units.

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Use of proceeds

We intend to use the net proceeds from this offering (after deducting underwriting discounts and commissions and estimated offering expenses) of approximately $              million and the approximately $              million capital contribution from our general partner to maintain its 2% general partner interest in us and any net proceeds from the underwriters' option to purchase additional common units for general partnership purposes, including repayment of outstanding borrowings under our revolving credit facility, working capital purposes and to finance potential future acquisitions.

We used the borrowings under our revolving credit facility primarily to fund capital expenditures and working capital requirements. In addition, in July 2012, we repaid the $100.0 million of 6.875% senior notes due July 15, 2012 with borrowings under our revolving credit facility. As of August 31, 2012, the outstanding balance of borrowings under our revolving credit facility was $705.2 million and the weighted average interest rate under the revolving credit facility was 1.9%. Our revolving credit facility is currently scheduled to mature on May 2, 2017.

Certain of the underwriters or their affiliates are lenders under our revolving credit facility and, in that respect, may receive a portion of the proceeds from this offering through the repayment of borrowings outstanding under our revolving credit facility. Please read "Underwriting (Conflicts of Interest)."

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Capitalization

The following table shows:

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NuStar Energy's historical cash and capitalization as of June 30, 2012;



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NuStar Energy's historical cash and capitalization on a pro forma basis to show the application of the estimated net proceeds from this offering and our general partner's contribution for general partnership purposes, as described under "Use of Proceeds"; and



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NuStar Energy's historical cash and capitalization on a pro forma as adjusted basis to give effect to the formation of the Asphalt JV, as described under "Summary—Recent Developments—Asphalt Joint Venture."

This table should be read together with the consolidated financial statements and the accompanying notes incorporated by reference in this prospectus supplement, including the unaudited financial statements included in the Quarterly Report on Form 10-Q for the quarter ended June 30, 2012 and

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our unaudited pro forma financial statements included in our Current Report on Form 8-K filed with the SEC on September 4, 2012.

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Price range of common units and distributions

Our common units are listed on the NYSE under the symbol "NS."

The following table sets forth, for the periods indicated, the high and low sales prices for our common units, as reported on the New York Stock Exchange Composite Transactions Tape, and quarterly cash distributions paid or to be paid to our unitholders. The last reported sales price of our common units on the NYSE on August 31, 2012 was $50.72 per common unit.

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Tax considerations

The tax consequences to you of an investment in our common units will depend in part on your own tax circumstances. For a discussion of the principal federal income tax considerations associated with our operations and the purchase, ownership and disposition of units, please read "Material Tax Consequences" beginning on page 47 of the accompanying base prospectus. The following discussion is limited and does not address certain holders, in each case as described under the caption "Material Tax Consequences" in the accompanying base prospectus. Please also read "Risk Factors" in this prospectus supplement and the accompanying base prospectus and "Risk Factors—Tax Risks to our Unitholders" in our Annual Report on Form 10-K for the year ended December 31, 2011 for a discussion of the tax risks related to purchasing and owning our common units. You are urged to consult your own tax advisor about the federal, state, foreign and local tax consequences particular to your circumstances.

Partnership tax treatment

The anticipated after-tax economic benefit of an investment in our common units depends largely on our being treated as a partnership for federal income tax purposes. We have not requested a ruling from the IRS with respect to our partnership status. In order to be treated as a partnership for federal income tax purposes, at least 90% of our gross income for every taxable year must be from specific qualifying sources, such as refining, processing, transportation, storage or marketing of crude oil, natural gas and products thereof or other types of passive income such as interest (other than from a financial business), dividends, gains from the sale of real property and gains from the sale or other disposition of capital assets held for the production of income that otherwise constitutes qualifying income. We estimate that less than 4% of our current gross income is not qualifying income, however, this estimate could change from time to time. For a more complete description of this qualifying income requirement, please read "Material Tax Consequences—Partnership Status" in the accompanying base prospectus.

If we were treated as a corporation for federal income tax purposes, we would pay federal income tax on our taxable income at the corporate tax rate, which is currently a maximum of 35%, and would likely pay state income tax at varying rates. Distributions to a unitholder would generally be taxed again as corporate distributions, and no income, gains, losses or deductions would flow through to the unitholders. Because a tax would be imposed upon us as a corporation, our cash available for distribution to the unitholders would be substantially reduced. Therefore, treatment of us as a corporation would result in a material reduction in the anticipated cash flow and after-tax return to the unitholders, likely causing a substantial reduction in the value of our common units.

Ratio of taxable income to distributions

We estimate that a purchaser of common units in this offering who owns those common units from the date of closing of this offering through the record date for distributions for the period ending December 31, 2015, will be allocated, on a cumulative basis, an amount of federal taxable income for that period that will be less than 20% of the cash distributed with respect to that period. Thereafter, we anticipate that the ratio of allocable taxable income to cash distributions to the unitholders will increase. These estimates are based upon many assumptions regarding our business and operations, including assumptions with respect to our capital expenditures, cash flow, net working capital and anticipated cash distributions. These estimates and assumptions are subject to, among other things, numerous business, economic, regulatory, competitive and political uncertainties beyond our control. Further, the estimates are based on current tax law and tax reporting positions that we have adopted and with which the IRS could disagree. Accordingly, we cannot assure you that these estimates will

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prove to be correct. The actual ratio of allocable taxable income to cash distributions could be higher or lower than expected, and any differences could be material and could materially affect the value of the common units. For example, the ratio of allocable taxable income to cash distributions to a purchaser of common units in this offering will be higher, and perhaps substantially higher, than our estimate with respect to the period described above if:

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gross income from operations exceeds the amount required to make the current level of distributions on all units, yet we only distribute the current level of distributions on all units; or

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we make a future offering of common units and use the proceeds of the offering in a manner that does not produce substantial additional deductions during the period described above, such as to repay indebtedness outstanding at the time of the offering or to acquire property that is not eligible for depreciation or amortization for federal income tax purposes or that is depreciable or amortizable at a rate significantly slower than the rate applicable to our assets at the time of this offering.

Tax-exempt organizations and other investors

Ownership of common units by tax-exempt entities, including employee benefit plans and individual retirement accounts (known as IRAs), and foreign investors raises issues unique to such persons. Please read "Material Tax Consequences—Tax-Exempt Organizations and Other Investors" in the accompanying base prospectus.

Tax rates

Under current law, the highest marginal U.S. federal income tax rate applicable to ordinary income of individuals is 35% and the highest marginal U.S. federal income tax rate applicable to long-term capital gains (generally, gains from the sale or exchange of certain investment assets held for more than one year) of individuals is 15%. However, absent new legislation extending the current rates, beginning January 1, 2013, the highest marginal U.S. federal income tax rate applicable to ordinary income and long-term capital gains of individuals will increase to 39.6% and 20%, respectively. Moreover, these rates are subject to change by new legislation at any time. A 3.8% Medicare tax on certain investment income earned by individuals will apply for taxable years beginning after December 31, 2012. For these purposes, investment income generally includes a unitholder's allocable share of our income and gain realized by a unitholder from a sale of units. The tax will be imposed on the lesser of (i) the unitholder's net income from all investments, and (ii) the amount by which the unitholder's adjusted gross income exceeds $250,000 (if the unitholder is married and filing jointly or a surviving spouse), $125,000 (if the unitholder is married and filing separately) or $200,000 (in any other case).

Nominee reporting

Persons who hold an interest in us as a nominee for another person are required to furnish to us:

(a)

the name, address and taxpayer identification number of the beneficial owner and the nominee;



(b)

a statement regarding whether the beneficial owner is:



1.

a non-U.S. person;



2.

a non-U.S. government, an international organization or any wholly owned agency or instrumentality of either of the foregoing; or



3.

a tax-exempt entity;

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(c)

the amount and description of units held, acquired or transferred for the beneficial owner; and



(d)

specific information including the dates of acquisitions and transfers, means of acquisitions and transfers, and acquisition cost for purchases, as well as the amount of net proceeds from sales.

Brokers and financial institutions are required to furnish additional information, including whether they are U.S. persons and specific information on units they acquire, hold or transfer for their own account. A penalty of $100 per failure, up to a maximum of $1.5 million per calendar year, is imposed by the Internal Revenue Code for failure to report that information to us. The nominee is required to supply the beneficial owner of the units with the information furnished to us.

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Underwriting (conflicts of interest)

Under the terms and subject to the conditions contained in an underwriting agreement dated the date of this prospectus supplement, the underwriters named below have agreed severally, and not jointly, to purchase, and we have agreed to sell, the number of common units set forth opposite each underwriter's name. UBS Securities LLC, Barclays Capital Inc., Credit Suisse Securities (USA) LLC, Deutsche Bank Securities Inc., J.P. Morgan Securities LLC, Morgan Stanley & Co. LLC, RBC Capital Markets, LLC and Wells Fargo Securities, LLC are acting as joint bookrunners and representatives of the other underwriters.

The underwriters are offering the common units subject to their acceptance of the common units from us and subject to prior sale. The underwriting agreement provides that the obligation of the underwriters to pay for and accept delivery of the common units offered by this prospectus supplement is subject to the approval of certain legal matters by their counsel and to certain other conditions. The underwriters are obligated to take and pay for all of the common units offered by this prospectus supplement if any such common units are taken. However, the underwriters are not required to take or pay for the common units covered by the underwriters' option to purchase additional common units described below.

The underwriters have advised us that they initially propose to offer part of the common units directly to the public at the public offering price listed on the cover page of this prospectus supplement and part to certain dealers at a price that represents a concession not in excess of $             per common unit under the public offering price. After the initial offering of the common units in this offering, the offering price and other selling terms may from time to time be varied by the underwriters. The offering of the common units by the underwriters is subject to receipt and acceptance and subject to the underwriters' right to reject any order in whole or in part. If an underwriter defaults, the underwriting agreement provides that the purchase commitments of the nondefaulting underwriters may be increased or the underwriting agreement may be terminated.

We have granted to the underwriters an option, exercisable for 30 days from the date of this prospectus supplement, to purchase up to an aggregate of 930,000 additional common units at the public offering price listed on the cover page of this prospectus supplement, less underwriting discounts and commissions. To the extent the option is exercised, each underwriter will become obligated,

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subject to certain conditions, to purchase about the same percentage of the additional common units as the number listed next to the underwriter's name in the table above bears to the total number of common units listed next to the names of all underwriters in the table above. The following table shows the underwriting discounts and commissions that we expect to pay to the underwriters in connection with this offering. These amounts are shown assuming both no exercise and full exercise of the underwriters' option to purchase additional common units.

William E. Greehey, the Chairman of the board of directors of NuStar GP, LLC, expects to purchase approximately 490,000 common units in this offering directly from the underwriters at a price equal to the public offering price. The underwriters will receive no underwriting discount or commission on the sale of these common units to Mr. Greehey.

We estimate that our aggregate expenses for this offering, excluding underwriters' discounts and commissions, will be approximately $300,000.

We, our general partner and certain of its affiliates, including the directors and officers of our general partner, have agreed not to, without the prior written consent of UBS Securities LLC, (1) offer for sale, sell, pledge, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, or otherwise transfer or dispose of, directly or indirectly, any common units or any securities which may be converted into or exercised or exchanged for any common units, (2) enter into any swap or other arrangement that transfers, in whole or in part, any of the economic consequences of ownership of the common units, (3) file any registration statement relating to the registration of any common units or securities convertible or exchangeable into common units, or (4) publicly disclose the intention to do any of these actions for a period of 45 days from the date of this prospectus supplement. The restrictions in this paragraph do not apply to the issuance of common units in connection with this offering, issuances of common units, or securities convertible into or exercisable or exchangeable for common units, pursuant to our general partner's incentive plans and sales of common units to satisfy tax withholding obligations under our general partner's incentive plans. UBS Securities LLC, in its sole discretion, may release the common units and the other securities subject to the lock-up agreements described above in whole or in part at any time with or without notice.

The common units are listed on the New York Stock Exchange under the symbol "NS."

In order to facilitate the offering of the common units, the underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of the common units. Specifically, the underwriters may over-allot in connection with the offering, creating a short position in the common units for its own account. In addition, to cover over-allotments or to stabilize the price of the common units, the underwriters may bid for, and purchase, common units in the open market. The underwriters may also impose a penalty bid. Finally, the underwriters may reclaim selling concessions allowed to the underwriters or a dealer for distributing the common units in the offering, if the syndicate repurchases previously distributed common units in transactions to cover syndicate short positions, in stabilization transactions or otherwise, as well as purchases by the underwriters for their own accounts. Any of these activities may stabilize or maintain the market price of the common units above independent market levels. The underwriters are not required to engage in these activities, and may end any of these activities without notice at any time.

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We, our general partner and certain affiliates have agreed to indemnify the several underwriters against certain liabilities, including liabilities under the Securities Act of 1933, as amended (the "Securities Act").

Because the Financial Industry Regulatory Authority, or FINRA, views the common units offered hereby as interests in a direct participation program, the offering is being made in compliance with Rule 2310 of the FINRA Rules. Investor suitability with respect to the common units should be judged similarly to the suitability with respect to other securities that are listed for trading on a national securities exchange.

The underwriters and their respective affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing and brokerage activities. In the ordinary course of their various business activities, the underwriters and their respective affiliates may make or hold a broad array of investments, including serving as counterparties to certain derivative and hedging arrangements, and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers and may at any time hold long and short positions in such securities and instruments. Such investment and securities activities may involve securities and instruments of the issuer.

Certain of the underwriters and their respective affiliates have performed, and may in the future perform, various financial advisory, investment banking and commercial banking services from time to time for us and our affiliates, for which they received or will receive customary fees and expense reimbursement. UBS Securities LLC, Barclays Capital Inc., Wells Fargo Securities, LLC, Credit Suisse Securities (USA) LLC, Deutsche Bank Securities Inc., J.P. Morgan Securities LLC and RBC Capital Markets, LLC Goldman, Sachs & Co., Morgan Stanley & Co. LLC, and Mitsubishi UFJ Securities (USA), Inc. or their affiliates are lenders under our revolving credit facility and, in that respect, may receive a portion of the proceeds from this offering upon the repayment of outstanding borrowings under that credit facility.

This prospectus supplement and the accompanying base prospectus may be used by the underwriters in connection with offers and sales of the common units in certain agented brokers' transactions; however, the underwriters are not obligated to engage in such agented brokers' transactions and may discontinue such activities without notice at any time.

Notice to Prospective Investors in the EEA

In relation to each member state of the European Economic Area that has implemented the Prospectus Directive (each, a relevant member state), with effect from and including the date on which the Prospectus Directive is implemented in that relevant member state (the relevant implementation date), an offer of securities described in this prospectus may not be made to the public in that relevant member state other than:

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to any legal entity which is a qualified investor as defined in the Prospectus Directive;

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to fewer than 100 or, if the Relevant Member State has implemented the relevant provision of the 2010 PD Amending Directive, 150, natural or legal persons (other than qualified investors as defined in the Prospectus Directive), as permitted under the Prospectus Directive, subject to obtaining the prior consent of the relevant Dealer or Dealers nominated by the Issuer for any such offer; or

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in any other circumstances falling within Article 3(2) of the Prospectus Directive;

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provided that no such offer of securities shall require us or any underwriter to publish a prospectus pursuant to Article 3 of the Prospectus Directive.

For purposes of this provision, the expression an "offer of securities to the public" in any relevant member state means the communication in any form and by any means of sufficient information on the terms of the offer and the securities to be offered so as to enable an investor to decide to purchase or subscribe for the securities, as the expression may be varied in that member state by any measure implementing the Prospectus Directive in that member state, and the expression "Prospectus Directive" means Directive 2003/71/EC (and amendments thereto, including the 2010 PD Amending Directive, to the extent implemented in the Relevant Member State), and includes any relevant implementing measure in the Relevant Member State, and includes any relevant implementing measure in each relevant member state. The expression "2010 PD Amending Directive" means Directive 2010/73/EU.

We have not authorized and do not authorize the making of any offer of securities through any financial intermediary on their behalf, other than offers made by the underwriters with a view to the final placement of the securities as contemplated in this prospectus. Accordingly, no purchaser of the securities, other than the underwriters, is authorized to make any further offer of the securities on behalf of us or the underwriters.

Notice to Prospective Investors in the United Kingdom

The Partnership may constitute a "collective investment scheme" as defined by section 235 of the Financial Services and Markets Act 2000 ("FSMA") that is not a "recognized collective investment scheme" for the purposes of FSMA ("CIS") and that has not been authorised or otherwise approved. As an unregulated scheme, it cannot be marketed in the United Kingdom to the general public, except in accordance with FSMA. This prospectus is only being distributed in the United Kingdom to, and is only directed at:

(i)

if the Partnership is a CIS and is marketed by a person who is an authorised person under FSMA, (a) investment professionals falling within Article 14(5) of the Financial Services and Markets Act 2000 (Promotion of Collective Investment Schemes) Order 2001, as amended (the "CIS Promotion Order") or (b) high net worth companies and other persons falling within Article 22(2)(a) to (d) of the CIS Promotion Order; or



(ii)

otherwise, if marketed by a person who is not an authorised person under FSMA, (a) persons who fall within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended (the "Financial Promotion Order") or (b) Article 49(2)(a) to (d) of the Financial Promotion Order; and



(iii)

in both cases (i) and (ii) to any other person to whom it may otherwise lawfully be made, (all such persons together being referred to as "relevant persons"). The Partnership's common units are only available to, and any invitation, offer or agreement to subscribe, purchase or otherwise acquire such common units will be engaged in only with, relevant persons. Any person who is not a relevant person should not act or rely on this document or any of its contents.

An invitation or inducement to engage in investment activity (within the meaning of Section 21 of FSMA) in connection with the issue or sale of any common units which are the subject of the offering contemplated by this prospectus will only be communicated or caused to be communicated in circumstances in which Section 21(1) of FSMA does not apply to the Partnership.

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Underwriting (Conflicts of Interest)

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Notice to Prospective Investors in Switzerland

This prospectus is being communicated in Switzerland to a small number of selected investors only. Each copy of this prospectus is addressed to a specifically named recipient and may not be copied, reproduced, distributed or passed on to third parties. Our common units are not being offered to the public in Switzerland, and neither this prospectus, nor any other offering materials relating to our common units may be distributed in connection with any such public offering. We have not been registered with the Swiss Financial Market Supervisory Authority FINMA as a foreign collective investment scheme pursuant to Article 120 of the Collective Investment Schemes Act of June 23, 2006 (CISA). Accordingly, our common units may not be offered to the public in or from Switzerland, and neither this prospectus, nor any other offering materials relating to our common units may be made available through a public offering in or from Switzerland. Our common units may only be offered and this prospectus may only be distributed in or from Switzerland by way of private placement exclusively to qualified investors (as this term is defined in the CISA and its implementing ordinance).

Notice to Prospective Investors in Germany

This document has not been prepared in accordance with the requirements for a securities or sales prospectus under the German Securities Prospectus Act (Wertpapierprospektgesetz), the German Sales Prospectus Act (Verkaufsprospektgesetz), or the German Investment Act (Investmentgesetz). Neither the German Federal Financial Services Supervisory Authority (Bundesanstalt für Finanzdienstleistungsaufsicht—BaFin) nor any other German authority has been notified of the intention to distribute our common units in Germany. Consequently, our common units may not be distributed in Germany by way of public offering, public advertisement or in any similar manner and this document and any other document relating to the offering, as well as information or statements contained therein, may not be supplied to the public in Germany or used in connection with any offer for subscription of our common units to the public in Germany or any other means of public marketing. Our common units are being offered and sold in Germany only to qualified investors which are referred to in Section 3, paragraph 2 no. 1, in connection with Section 2, no. 6, of the German Securities Prospectus Act, Section 8f paragraph 2 no. 4 of the German Sales Prospectus Act, and in Section 2 paragraph 11 sentence 2 no. 1 of the German Investment Act. This document is strictly for use of the person who has received it. It may not be forwarded to other persons or published in Germany.

The offering does not constitute an offer to sell or the solicitation or an offer to buy our common units in any circumstances in which such offer or solicitation is unlawful.

Notice to Prospective Investors in the Netherlands

Our common units may not be offered or sold, directly or indirectly, in the Netherlands, other than to qualified investors (gekwalificeerde beleggers) within the meaning of Article 1:1 of the Dutch Financial Supervision Act (Wet op het financieel toezicht).

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Legal

The validity of the common units will be passed upon for us by Andrews Kurth LLP, Houston, Texas. Certain legal matters in connection with the common units offered hereby will be passed upon for the underwriters by Baker Botts L.L.P., Houston, Texas.

Experts

The consolidated financial statements of NuStar Energy L.P. as of December 31, 2011 and 2010, and for each of the years in the three-year period ended December 31, 2011, and management's assessment of the effectiveness of internal control over financial reporting as of December 31, 2011 have been incorporated by reference herein and in the registration statement in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

Forward looking statements

Certain matters discussed in this prospectus and the documents incorporated herein by reference, excluding historical information, contain certain estimates, predictions, assumptions and other forward-looking statements that involve risks and uncertainties. While these forward-looking statements, and any assumptions upon which they are based, are made in good faith and reflect our current judgment regarding the direction of our business, actual results will almost always vary, sometimes materially, from any estimates, predictions, projections, assumptions or other future performance suggested in this prospectus.

Forward-looking statements can generally be identified by words such as "anticipates," "believes," "budgets," "could," "estimates," "expects," "forecasts," "intends," "plans," "projects," and "should" or similar expressions. Similarly, statements that describe our future plans, objectives or goals are also forward-looking statements.

Although we believe these forward-looking statements are based on reasonable assumptions, statements made regarding future results are subject to a number of assumptions, uncertainties and risks that may cause future results to be materially different from the results stated or implied in this prospectus or the documents incorporated herein by reference. These risks and uncertainties include, among other things:

–>

any significant decrease in the amount of crude oil, refined products and anhydrous ammonia transported in our pipelines;

–>

any significant decrease in the throughput volumes in our terminals and storage facilities;

–>

the exposure to trading losses and hedging losses as a result of the marketing and trading of refined products, and any non-compliance with our risk management policies;

–>

any significant decrease in the demand for crude oil, refined products and anhydrous ammonia;

–>

the effect of worldwide energy conservation measures;

–>

any significant increase in our operating costs;

–>

any changes in laws and regulations to which we are subject, including federal, state and local tax laws, safety, environmental and employment laws;

–>

actions by regulatory agencies;

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Forward looking statements

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–>

the volatility of commodity prices;

–>

the closing of the sale of the 50% interest in the Asphalt JV;

–>

the seasonality of the Asphalt JV's business and associated working capital requirements;

–>

our significant leverage and restrictions in our debt agreements and additional ratings downgrades, if any;

–>

any substantial costs related to environmental risks, including increased costs of compliance;

–>

terrorist attacks, threat of war or terrorist attacks or political or other disruptions that limit crude oil production; and

–>

accidents, shutdowns or closures affecting our pipelines, terminals, machinery or equipment.

Additional information about risks and uncertainties that could cause actual results to differ materially from those contained in any forward-looking statements is contained under the caption "Risk Factors" in this prospectus supplement and the accompanying base prospectus, in Item 1A of Part I of our Annual Report on Form 10-K for the year ended December 31, 2011 and in our other filings with the SEC that are incorporated herein by reference. The forward-looking statements included in this prospectus supplement and the documents incorporated herein by reference are only made as of the date of such documents and, except as required by securities laws, we undertake no obligation to publicly update forward-looking statements to reflect subsequent events or circumstances.

Where you can find more information

We have filed a registration statement with the SEC under the Securities Act that registers the offer and sale of the common units covered by this prospectus supplement. The registration statement, including the attached exhibits, contains additional relevant information about us. In addition, we file annual, quarterly and other reports and other information with the SEC. You may read and copy any document we file with the SEC at the SEC's Public Reference Room at 100 F Street, N.E., Room 1580, Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the operation of the SEC's Public Reference Room. The SEC maintains an Internet site that contains reports, proxy and information statements and other information regarding issuers that file electronically with the SEC. Our SEC filings are available on the SEC's web site at http://www.sec.gov. You also can obtain information about us at the offices of the New York Stock Exchange, 20 Broad Street, New York, New York 10005.

The SEC allows us to "incorporate by reference" information into this prospectus supplement. This means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is considered to be part of this prospectus supplement, and information that we file later with the SEC will automatically update and supersede the previously filed information. We incorporate by reference the documents listed below and any future filings made by us with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, other than any portions of the respective filings that are furnished, pursuant to Item 2.02 or Item 7.01 of Current Report on Form 8-K (including exhibits related thereto) or other applicable SEC rules, rather than filed, prior to the completion or termination of the offering under this prospectus supplement.

–>

Annual Report on Form 10-K (File No. 001-16417) for the year ended December 31, 2011;

–>

Quarterly Reports on Form 10-Q (File No. 001-16417) for the quarters ended March 31, 2012 and June 30, 2012;

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Where you can find more information

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–>

Current Reports on Form 8-K (File No. 001-16417) filed on January 30, 2012, January 31, 2012, February 1, 2012; February 7, 2012, May 8, 2012, June 12, 2012, July 6, 2012 and September 4, 2012; and

–>

The description of our common units contained in our registration statement on Form 8-A (File No. 001-16417) filed on March 30, 2001, including any amendments or reports filed for the purpose of updating such description.

Each of these documents is available from the SEC's website and public reference rooms described above. Through our website http://www.nustarenergy.com, you can access electronic copies of documents we file with the SEC, including our annual reports on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K and any amendments to those reports. Information on our website is not incorporated by reference in this prospectus supplement. Access to those electronic filings is available as soon as practical after filing with the SEC. You may also request a copy of those filings, excluding exhibits, at no cost by writing or telephoning Investor Relations, NuStar Energy L.P., at our principal executive office, which is: 2330 North Loop 1604 West, San Antonio, Texas 78248; Telephone (210) 918-2000.

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PROSPECTUS

NUSTAR ENERGY L.P.
Common Units Representing Limited Partner Interests

NUSTAR LOGISTICS, L.P.
Debt Securities

NUSTAR PIPELINE OPERATING PARTNERSHIP, L.P.
Debt Securities

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        NuStar Energy L.P. may, in one or more offerings, offer and sell common units representing limited partner interests in NuStar Energy L.P. NuStar Energy L.P. common units are listed for trading on the New York Stock Exchange under the symbol "NS."

        NuStar Logistics, L.P. may, in one or more offerings, offer and sell its debt securities, which will be fully and unconditionally guaranteed by one or more of us or NuStar Pipeline Operating Partners, L.P.

        NuStar Pipeline Operating Partners, L.P. may, in one or more offerings, offer and sell its debt securities, which will be fully and unconditionally guaranteed by one or more of us or NuStar Logistics, L.P.

        We will provide information in the related prospectus supplement for the trading market, if any, for any debt securities NuStar Logistics, L.P. or NuStar Pipeline Operating Partners, L.P. may offer.

        We will offer the securities in amounts and at prices and on terms to be determined by market conditions and other factors at the time of our offerings. This prospectus describes only the general terms of these securities and the general manner in which we will offer the securities. The specific terms of any securities we offer will be included in a supplement to this prospectus. The prospectus supplement will describe the specific manner in which we will offer the securities, and also may add, update or change information contained in this prospectus.

        You should read this prospectus and the applicable prospectus supplement and the documents incorporated by reference herein and therein carefully before you invest in our securities. This prospectus may not be used to consummate sales of securities unless accompanied by a prospectus supplement.

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        Investing in these securities involves a high degree of risk. Limited partnerships are inherently different from corporations. For a discussion of the factors you should consider before deciding to purchase these securities, please see "Risk Factors," beginning on page 4 of this prospectus.

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        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is May 13, 2010.

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        You should rely only on the information contained in this prospectus, any prospectus supplement and the documents we have incorporated by reference. We have not authorized anyone to provide you with different information. We are not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information contained in this prospectus or any prospectus supplement, as well as the information we previously filed with the Securities and Exchange Commission that is incorporated by reference herein, is accurate as of any date other than its respective date.

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ABOUT THIS PROSPECTUS

        The information contained in this prospectus is not complete and may be changed. You should rely only on the information provided in or incorporated by reference in this prospectus, any prospectus supplement, or documents to which we otherwise refer you. We have not authorized anyone else to provide you with different information. We are not making an offer of any securities in any jurisdiction where the offer is not permitted. You should not assume that the information in this prospectus, any prospectus supplement or any document incorporated by reference is accurate as of any date other than the date of the document in which such information is contained or such other date referred to in such document, regardless of the time of any sale or issuance of a security.

        This prospectus is part of a registration statement that we have filed with the Securities and Exchange Commission, or SEC, utilizing a "shelf" registration process. Under this shelf registration process, we may, over time, offer and sell any combination of the securities described in this prospectus in one or more offerings. This prospectus provides you with a general description of the securities we may offer. Each time we sell securities, we will provide a prospectus supplement that will contain specific information about the terms of that offering and the securities offered by us in that offering. The prospectus supplement may also add, update or change information in this prospectus. You should read both this prospectus and any prospectus supplement together with additional information described under the headings "Where You Can Find More Information" and "Incorporation by Reference."

        This prospectus contains summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by reference to the actual documents. Copies of some of the documents referred to herein have been filed or will be filed or incorporated by reference as exhibits to the registration statement of which this prospectus is a part, and you may obtain copies of those documents as described below in the section entitled "Where You Can Find More Information."

        In this prospectus, references to "NuStar Energy," "we," "us" and "our" mean NuStar Energy L.P. and its consolidated subsidiaries, unless otherwise noted. References to "NuStar Logistics" mean NuStar Logistics, L.P. References to "NPOP" mean NuStar Pipeline Operating Partnership, L.P.

ABOUT NUSTAR ENERGY L.P., NUSTAR LOGISTICS, L.P. AND NUSTAR PIPELINE OPERATING PARTNERSHIP, L.P.

        NuStar Energy is a publicly held Delaware limited partnership engaged in the terminalling and storage of petroleum products, the transportation of petroleum products and anhydrous ammonia, and asphalt and fuels marketing. We conduct our operations through our wholly owned subsidiaries, primarily NuStar Logistics and NPOP.

        Our operations are managed by NuStar GP, LLC, the general partner of Riverwalk Logistics, L.P., our general partner. NuStar GP, LLC is a wholly owned subsidiary of NuStar GP Holdings, LLC, a publicly traded limited liability company (NYSE: NSH).

        Our principal executive offices are located at 2330 North Loop 1604 West, San Antonio, Texas 78248, and our telephone number is (210) 918-2000.

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WHERE YOU CAN FIND MORE INFORMATION

        We, NuStar Logistics and NPOP have filed with the Securities and Exchange Commission a registration statement on Form S-3 under the Securities Act of 1933, as amended (the Securities Act), regarding the common units and debt securities. This prospectus does not contain all of the information found in the registration statement. For further information regarding us and the securities offered by this prospectus, you may desire to review the full registration statement, including its exhibits and schedules, filed under the Securities Act. The registration statement of which this prospectus forms a part, including its exhibits and schedules, may be inspected and copied at the public reference room maintained by the SEC at 100 F Street, N.E., Room 1580, Washington, D.C. 20549. Copies of the materials may also be obtained from the SEC at prescribed rates by writing to the public reference room maintained by the SEC at 100 F Street, N.E., Room 1580, Washington, D.C. 20549. You may obtain information on the operation of the public reference room by calling the SEC at 1-800-SEC-0330.

        The SEC maintains a website on the Internet at http://www.sec.gov. Our registration statement, of which this prospectus constitutes a part, can be downloaded from the SEC's website and can also be inspected and copied at the offices of the New York Stock Exchange, Inc., 20 Broad Street, New York, New York 10005.

        You should rely only on the information contained in this prospectus. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We are not making an offer to sell these securities in any jurisdiction where an offer or sale is not permitted. You should assume that the information appearing in this prospectus is accurate as of the date on the front cover of this prospectus only. Our business, financial condition, results of operations and prospects may have changed since that date.

        NuStar Logistics and NPOP are not reporting companies under the Securities Exchange Act of 1934, as amended. However, we file with or furnish to the SEC periodic reports and other information. These reports and other information may be inspected and copied at the public reference facilities maintained by the SEC or obtained from the SEC's website as provided above. NuStar Energy's website on the Internet is located at http://www.nustarenergy.com and NuStar Energy makes its periodic reports and other information filed with or furnished to the SEC available, free of charge, through its website, as soon as reasonably practicable after those reports and other information are electronically filed with or furnished to the SEC. Information on NuStar Energy's website is not incorporated by reference into this prospectus and does not constitute a part of this prospectus.

        NuStar Energy intends to furnish or make available to its unitholders annual reports containing our audited financial statements and furnish or make available to its unitholders quarterly reports containing our unaudited interim financial information, including the information required by Form 10-Q, for the first three quarters of each fiscal year.

INCORPORATION BY REFERENCE

        The SEC allows us to "incorporate by reference" information into this document. This means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is considered to be part of this prospectus, and information that we file later with the SEC will automatically update and supersede the previously filed information. We incorporate by reference the documents filed by NuStar Energy that are listed below and any future filings made by NuStar Energy with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, excluding information deemed to be furnished and not filed with the SEC, until all the securities are sold, prior to the termination of the offerings under this prospectus:

•

Registration Statement on Form 8-A (File No. 001-16417) filed on March 30, 2001;

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•

Annual Report on Form 10-K (File No. 001-16417) for the year ended December 31, 2009, filed on February 26, 2010;



•

Quarterly Report on Form 10-Q (File No. 001-16417) for the quarter ended March 31, 2010, filed on May 6, 2010; and



•

Current Reports on Form 8-K (File No. 001-16417) filed on February 2, 2010 and March 2, 2010.

        Each of these documents is available from the SEC's website and public reference rooms described above. Through our website, http://www.nustarenergy.com, you can access electronic copies of documents we file with the SEC, including our annual reports on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K and any amendments to those reports. Information on our website is not incorporated by reference in this prospectus. Access to those electronic filings is available as soon as practical after filing with the SEC. You may also request a copy of those filings, excluding exhibits, at no cost by writing or telephoning Investor Relations, NuStar Energy L.P., at our principal executive office, which is: 2330 North Loop 1604 West, San Antonio, Texas 78248; Telephone (210) 918-2000.

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RISK FACTORS

        Limited partner interests are inherently different from the capital stock of a corporation, although many of the business risks to which we are subject are similar to those that would be faced by a corporation engaged in a similar business. Before you invest in our securities, you should carefully consider the risk factors included in our most-recent annual report on Form 10-K, in our quarterly reports on Form 10-Q and in our current reports on Form 8-K that are incorporated herein by reference and those that may be included in the applicable prospectus supplement, together with all of the other information included in this prospectus, any prospectus supplement and the documents we incorporate by reference.

        If any of the risks discussed in the foregoing documents were actually to occur, our business, financial condition, results of operations, or cash flow could be materially adversely affected. In that case, our ability to make distributions to our unitholders or pay interest on, or the principal of, any debt securities, may be reduced, the trading price of our securities could decline and you could lose all or part of your investment.

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FORWARD-LOOKING STATEMENTS AND ASSOCIATED RISKS

        Some of the information contained in or incorporated by reference in this prospectus may contain forward-looking statements. These statements can be identified by the use of forward-looking terminology including "may," "believe," "will," "expect," "anticipate," "estimate," "continue," "intend," "forecast," "project," "potential" or other similar words. These statements discuss future expectations, contain projections of results of operations or of financial condition, or state other "forward-looking" information. These forward-looking statements involve risks and uncertainties. When considering these forward-looking statements, you should keep in mind the risk factors and other cautionary statements in this prospectus or incorporated by reference herein, including those described in the "Risk Factors" section of our most recent annual report on Form 10-K and, to the extent applicable, our quarterly reports on Form 10-Q, our current reports on Form 8-K and any prospectus supplement. The risk factors and other factors noted in this prospectus or incorporated by reference herein could cause our actual results to differ materially from those contained in any forward-looking statement. Investors are cautioned that certain statements contained in or incorporated by reference in this prospectus as well as some statements in periodic press releases and some oral statements made by our officials and our subsidiaries during presentations about us, are "forward-looking" statements. Forward-looking statements are based on current expectations and projections about future events and are inherently subject to a variety of risks and uncertainties, many of which are beyond our control, that could cause actual results to differ materially from those anticipated or projected. You are cautioned not to place undue reliance on such forward-looking statements.

        Forward-looking statements speak only as of the date of this prospectus or, in the case of forward-looking statements contained in any document incorporated by reference, the date of such document and we expressly disclaim any obligation or undertaking to update these statements to reflect any change in our expectations or beliefs or any change in events, conditions or circumstances on which any forward-looking statement is based.

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RATIO OF EARNINGS TO FIXED CHARGES

        The following table sets forth our ratios of earnings to fixed charges for the periods indicated.

        For purposes of calculating the ratio of earnings to fixed charges:

•

"fixed charges" represent interest expense (including amounts capitalized and amortization of debt costs) and the portion of rental expense representing the interest factor; and



•

"earnings" represent the aggregate of pre-tax income from continuing operations (before adjustment for income from equity investees), fixed charges, amortization of capitalized interest and distributions from equity investees, less capitalized interest.

USE OF PROCEEDS

        Unless otherwise indicated in an accompanying prospectus supplement, NuStar Energy, NuStar Logistics and NPOP expect to use the net proceeds from the sale of NuStar Energy common units and NuStar Logistics and NPOP debt securities, as the case may be, for general partnership purposes, which may include, among other things:

•

the repayment of outstanding indebtedness;



•

working capital;



•

capital expenditures; and



•

acquisitions.

        The actual application of proceeds we receive from the sale of any particular offering of securities using this prospectus will be described in the applicable prospectus supplement relating to such offering.

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DESCRIPTION OF NUSTAR ENERGY COMMON UNITS

Number of Units

        As of May 1, 2010, we had 60,210,549 common units outstanding, of which 10,223,020 are held by our general partner and its affiliates. The common units represent an aggregate 98% limited partner interest in NuStar Energy and the general partner has a 2% general partner interest in NuStar Energy.

        Under our partnership agreement we may issue, without further unitholder action, an unlimited number of additional limited partner interests and other equity securities with such rights, preferences and privileges as may be established by our general partner in its sole discretion.

Voting

        Each holder of common units is entitled to one vote for each common unit on all matters submitted to a vote of the unitholders; provided that, if at any time any person or group, except our general partner, owns beneficially 20% or more of all common units, the common units so owned may not be voted on any matter and may not be considered to be outstanding when sending notices of a meeting of unitholders (unless otherwise required by law), calculating required votes, determining the presence of a quorum or for other similar purposes under our partnership agreement.

        Removal of our general partner requires:

•

a vote of not less than a majority of all outstanding common units, excluding the common units held by affiliates of our general partner; and



•

the election of a successor general partner by the holders of a majority of the outstanding common units, excluding the units held by affiliates of our general partner.

Listing

        Our outstanding common units are listed on The New York Stock Exchange (NYSE) under the symbol "NS." Any additional common units we issue will also be listed on the NYSE.

Transfer Agent and Registrar

        Our transfer agent and registrar for the common units is Computershare, LLC.

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CASH DISTRIBUTIONS

Distributions of Available Cash

General

        Within 45 days after the end of each quarter, NuStar Energy will distribute all of its available cash to its partners of record on the applicable record date.

Definition of Available Cash

        Available cash is defined in NuStar Energy's partnership agreement and generally means, with respect to any fiscal quarter, the sum of all cash and cash equivalents on hand at the end of such quarter, plus any working capital borrowings made subsequent to the end of such quarter, less the amount of any cash reserves that NuStar Energy's general partner deems necessary or appropriate to:

•

provide for the proper conduct of NuStar Energy's business, including reserves for future capital expenditures and anticipated credit needs;



•

comply with applicable law or any debt instrument or other agreement or obligation; or



•

provide funds for distributions with respect to any one or more of the next four fiscal quarters.

Intent to Distribute the Minimum Quarterly Distribution

        NuStar Energy's policy is, to the extent it has sufficient available cash from operating surplus, as defined below, to distribute to each common unit at least the minimum quarterly distribution of $0.60 per quarter or $2.40 per year. However, there is no guarantee that NuStar Energy will pay the minimum quarterly distribution on the common units in any quarter and NuStar Energy may be prohibited from making any distributions to unitholders if it would cause an event of default under the terms of NuStar Energy's indebtedness.

Operating Surplus and Capital Surplus

General

        Cash distributions are characterized as distributions from either operating surplus or capital surplus. NuStar Energy distributes available cash from operating surplus differently than available cash from capital surplus.

Definition of Operating Surplus

        Operating surplus is defined in NuStar Energy's partnership agreement and generally means, with respect to any period ending prior to the dissolution of NuStar Energy:

•

$10 million plus all cash and cash equivalents on hand as of the close of business on April 16, 2001, the closing date of its initial public offering of its common units;



•

plus all cash receipts since April 16, 2001, other than from interim capital transactions such as borrowings that are not working capital borrowings, sales of equity and debt securities and sales or other dispositions of assets for cash, other than inventory, accounts receivable and other assets sold in the ordinary course of business or as part of normal retirements or replacements of assets;



•

plus all cash receipts resulting from working capital borrowings after the end of such period but on or before the date of determination of the operating surplus for such period;



•

less all operating expenditures since April 16, 2001; and



•

less the amount of cash reserves that NuStar Energy's general partner deems necessary or advisable to provide funds for future operating expenditures.

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Definition of Capital Surplus

        Capital surplus of NuStar Energy will generally be generated only by:

•

borrowings other than working capital borrowings;



•

sales of debt and equity securities; and



•

sales or other dispositions of assets for cash, other than inventory, accounts receivable and other current assets sold in the ordinary course of business or as part of normal retirements or replacements of assets.

Characterization of Cash Distributions

        To avoid the difficulty of trying to determine whether the available cash that NuStar Energy distributes is from operating surplus or from capital surplus, all available cash that NuStar Energy distributes on any date from any source is treated as a distribution of cash from operating surplus until the sum of all available cash theretofore distributed equals the operating surplus calculated as of the end of the fiscal quarter with respect to which such distribution is being made. Any remaining amounts of available cash distributed on such date will be treated as cash from capital surplus and will be distributed accordingly.

        If at any time (i) a hypothetical holder of a common unit acquired on April 16, 2001 has received distributions of available cash from capital surplus in an aggregate amount equal to the $24.50 initial public offering price of the common units, and (ii) each common unit then outstanding has received an amount equal to any cumulative arrearage existing with respect to the common units, then the distinction between operating surplus and capital surplus will cease, and all subsequent distributions of available cash will be treated as distributions of cash from operating surplus and will be distributed accordingly. To date there have been no distributions from capital surplus, and NuStar Energy does not anticipate that there will be significant distributions from capital surplus in the future.

Distributions of Available Cash from Operating Surplus

        NuStar Energy will make distributions of available cash from operating surplus as follows:

•

First, 98% to the unitholders, pro rata, and 2% to the general partner, until NuStar Energy has distributed for each outstanding unit an amount equal to the minimum quarterly distribution of $0.60 for that quarter;



•

Second, 90% to all unitholders, pro rata, 8% to the holders of the incentive distribution rights, and 2% to the general partner, until NuStar Energy has distributed with respect to each unit then outstanding an amount equal to the excess of the first target distribution ($0.66 per unit) over the minimum quarterly distribution; and



•

Thereafter, 75% to all unitholders, pro rata, 23% to the holders of the incentive distribution rights, and 2% to the general partner.

        If the minimum quarterly distribution and the first target distribution have been reduced to zero under the terms of the partnership agreement, then any distribution of available cash from operating surplus will be made solely in accordance with the final bullet point above.

        The minimum quarterly distribution and the first target distribution are subject to adjustment as described below in "—Adjustment of the Minimum Quarterly Distribution and Target Distribution Levels."

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Distributions of Available Cash from Capital Surplus

How Distributions from Capital Surplus are Made

        NuStar Energy makes distributions of available cash from capital surplus in the following manner:

•

First, 98% to all unitholders, pro rata, and 2% to the general partner, until a hypothetical holder of a common unit acquired on April 16, 2001 has received an aggregate amount equal to the $24.50 initial public offering price of the common units;



•

Second, 98% to the common unitholders, pro rata, and 2% to the general partner, until there has been distributed with respect to each common unit then outstanding an amount equal to any cumulative arrearage existing with respect to the common units; and



•

Thereafter, all distributions of available cash from capital surplus will be distributed as if they were from operating surplus.

Effect of a Distribution from Capital Surplus

        NuStar Energy's partnership agreement treats a distribution of cash from capital surplus on a common unit as the repayment of the initial public offering price of such common unit, which is a return of capital. The initial public offering price less any distributions of cash from capital surplus per common unit is referred to as "unrecovered initial unit price" or "unrecovered capital." Each time a distribution of cash from capital surplus is made on a common unit, the minimum quarterly distribution and the first target distribution for all units will be reduced in the same proportion as the corresponding reduction in the unrecovered capital. Because distributions of cash from capital surplus will reduce the minimum quarterly distribution, after any of these distributions are made, it may be easier for NuStar Energy's general partner to receive incentive distributions. However, any distribution by NuStar Energy of capital surplus before the unrecovered capital is reduced to zero cannot be applied to the payment of the minimum quarterly distribution or any arrearages.

        If at any time NuStar Energy makes a distribution of cash from capital surplus in an amount equal to the then current unrecovered capital, the minimum quarterly distribution and the first target distribution will be reduced to zero. As a result, all future distributions will be made from operating surplus, with 75% being paid to all unitholders, pro rata, 23% to the general partner as the holder of incentive distribution rights, pro rata, and 2% to the general partner.

Incentive Distribution Rights

        Incentive distribution rights are non-voting limited partner interests that were issued to NuStar Energy's general partner in connection with the transfer of its general partnership interest in the operating partnership to NuStar Energy. Incentive distribution rights represent the right to receive an increasing percentage of quarterly distributions of available cash from operating surplus after the minimum quarterly distribution has been achieved. The general partner as the holder of incentive distribution rights is paid in the manner described in "—Distributions of Available Cash from Operating Surplus" above.

        Prior to March 31, 2011, the general partner may not transfer (other than to affiliates, in a merger or the sale of all assets) the incentive distribution rights without the approval of the majority of the common units (excluding the general partner's common units) then outstanding.

Adjustment of the Minimum Quarterly Distribution and Target Distribution Levels

        NuStar Energy's minimum quarterly distribution is $0.60 per unit, subject to adjustment. NuStar Energy's first target distribution is $0.66 per unit, subject to adjustment. NuStar Energy has no other target distribution levels.

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        In addition to reductions of the minimum quarterly distribution and first target distribution level made upon a distribution of available cash from capital surplus, as described above, if NuStar Energy distributes units to its unitholders, combines its units into fewer units or subdivides its units into a greater number of units, NuStar Energy will proportionately adjust:

•

the minimum quarterly distribution;



•

the first target distribution level;



•

any common unit arrearage;



•

any cumulative common unit arrearage; and



•

the unrecovered capital.

        For example, in the event of a two-for-one split of the common units (assuming no prior adjustments), the minimum quarterly distribution, the first target distribution level, any common unit arrearage, any cumulative common unit arrearage and the unrecovered capital of the common units would each be reduced to 50% of its initial level.

        In addition, if legislation is enacted or if existing law is modified or interpreted in a manner that causes NuStar Energy and/or the operating partnership to become taxable as a corporation or otherwise subject to taxation as an entity for federal, state or local income tax purposes, then NuStar Energy will reduce the then-applicable minimum quarterly distribution and the first target distribution level by multiplying the same by one minus the sum of (a) the highest marginal federal corporate (or other) income tax rate that could apply plus (b) any increase in the effective overall state and local income tax rates. For example, if NuStar Energy became subject to a maximum effective federal, state and local income tax rate of 35%, then the minimum quarterly distribution and the first target distribution level would each be reduced to 65% of their previous levels.

Distributions of Cash upon Liquidation

        If NuStar Energy dissolves in accordance with its partnership agreement, it will sell or otherwise dispose of its assets in a process called a liquidation, and the partner's capital account balances will be adjusted to reflect any resulting gain or loss. NuStar Energy will first apply the proceeds of liquidation to the payment of its creditors (including partners) in the order of priority provided in the partnership agreement and by law and, thereafter, it will distribute any remaining proceeds to its partners in accordance with, and to the extent of, the positive balances in their respective capital accounts, as adjusted. The manner of adjustment of capital accounts is set forth in NuStar Energy's partnership agreement.

Manner of Adjustments for Gain

        Upon its liquidation, NuStar Energy will allocate any net gain (or unrealized gain attributable to assets distributed in kind to the partners) in the following manner:

•

first, to each partner having a negative balance in its capital account, in the proportion that such negative balance bears to the total negative balances of all partners, until each partner has been allocated net gain equal to its negative balance;



•

second, 98% to the common unitholders, pro rata, and 2% to the general partner, until the capital account for each common unit then outstanding is equal to the sum of:



•

the unrecovered capital with respect to such common unit;



•

the amount of any unpaid minimum quarterly distribution for the quarter during which the liquidation occurs; and



•

the amount of any cumulative arrearage existing with respect to the common units;

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•

third, 90% to all unitholders, pro rata, 8% to the holders of the incentive distribution rights, pro rata, and 2% to the general partner, until the capital account for each common unit then outstanding is equal to the sum of:



•

the unrecovered capital with respect to each common unit;



•

the amount of any unpaid minimum quarterly distribution for the quarter during which the liquidation occurs;



•

the amount of any cumulative arrearage existing with respect to the common units; and



•

the excess of (a) the first target distribution less the minimum quarterly distribution for each quarter of the partnership's existence, over (b) the cumulative per unit amount of any distributions of available cash from operating surplus that were distributed 90% to all unitholders, pro rata, 8% to the holders of incentive distribution rights, pro rata, and 2% to the general partner; and



•

thereafter, 75% to all unitholders, pro rata, 23% to the holders of incentive distribution rights, pro rata, and 2% to the general partner.

Manner of Adjustments for Losses

        Upon its liquidation, NuStar Energy will allocate any loss in the following manner:

•

first, 98% to the common unitholders, pro rata, and 2% to the general partner, until the capital account for each common unit has been reduced to zero; and



•

thereafter, 100% to the general partner.

Adjustments to Capital Accounts

        In addition, interim adjustments to capital accounts will be made at the time NuStar Energy issues additional partnership interests or makes distributions of property. Such adjustments will be based on the fair market value of the partnership interests or the property distributed and any gain or loss resulting therefrom will be allocated to the partners in the same manner as gain or loss is allocated upon liquidation. In the event that positive interim adjustments are made to the capital accounts, any subsequent negative adjustments to the capital accounts resulting from the issuance of additional partnership interests in NuStar Energy, distributions of property by NuStar Energy, or upon NuStar Energy's liquidation, will be allocated in a manner which results, to the extent possible, in the capital account balances of the general partner equaling the amount that would have been the general partner's capital account balances if no prior positive adjustments to the capital accounts had been made.

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THE PARTNERSHIP AGREEMENT

        The following is a summary of the material provisions of the NuStar Energy partnership agreement. NuStar Energy's partnership agreement is included as an exhibit to the registration statement of which this prospectus constitutes a part.

Organization and Duration

        NuStar Energy was organized in December 1999 and will continue until dissolved under the terms of its partnership agreement.

Purpose

        NuStar Energy's stated purposes under its partnership agreement are to serve as a partner of its operating partnerships and to engage in any business activities that may be engaged in by its operating partnerships or that are approved by the general partner, provided that the general partner must reasonably determine that such activity generates or enhances the operations of an activity that generates "qualifying income," as this term is defined in Section 7704 of the Internal Revenue Code.

        NuStar Energy's general partner is authorized in general to perform all acts deemed necessary to carry out NuStar Energy's purposes and to conduct NuStar Energy's business.

Power of Attorney

        Each limited partner, and each person who acquires a unit from a unitholder and executes and delivers a transfer application, grants to the general partner and, if appointed, a liquidator, a power of attorney to, among other things, execute and file documents required for the qualification, continuance or dissolution of NuStar Energy. The power of attorney also grants the general partner and the liquidator the authority to amend the partnership agreement, and to make consents and waivers under the partnership agreement.

Capital Contributions

        NuStar Energy's unitholders are not obligated to make additional capital contributions, except as described below under "—Limited Liability."

Limited Liability

        Assuming that a limited partner does not participate in the control of NuStar Energy's business within the meaning of the Delaware Revised Uniform Limited Partnership Act, which we refer to in this prospectus as the Delaware law, and that he otherwise acts in conformity with the provisions of NuStar Energy's partnership agreement, his liability under the Delaware law will be limited, subject to possible exceptions, to the amount of capital he is obligated to contribute to NuStar Energy for his common units plus his share of any undistributed profits and assets. If it were determined, however, that the right or exercise of the right by the NuStar Energy limited partners as a group:

•

to remove or replace the general partner;



•

to approve some amendments to the partnership agreement; or



•

to take other action under the partnership agreement;

constituted "participation in the control" of NuStar Energy's business for the purposes of the Delaware law, then the limited partners could be held personally liable for NuStar Energy's obligations under the laws of Delaware, to the same extent as the general partner. This liability would extend to persons who transact business with NuStar Energy who reasonably believe that the limited partner is a general partner.

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        Neither NuStar Energy's partnership agreement nor the Delaware law specifically provides for legal recourse against the general partner if a limited partner were to lose limited liability through any fault of the general partner. While this does not mean that a limited partner could not seek legal recourse, we know of no precedent for this type of a claim in Delaware case law.

        Under the Delaware law, a limited partnership may not make a distribution to a partner if, after the distribution, all liabilities of the limited partnership, other than liabilities to partners on account of their partnership interests and liabilities for which the recourse of creditors is limited to specific property of the partnership, would exceed the fair value of the assets of the limited partnership. For the purpose of determining the fair value of the assets of a limited partnership, the Delaware law provides that the fair value of property subject to liability for which recourse of creditors is limited shall be included in the assets of the limited partnership only to the extent that the fair value of that property exceeds the nonrecourse liability. The Delaware law provides that a limited partner who receives a distribution and knew at the time of the distribution that the distribution was in violation of the Delaware law shall be liable to the limited partnership for the amount of the distribution for three years. Under the Delaware law, an assignee who becomes a substituted limited partner of a limited partnership is liable for the obligations of his assignor to make contributions to the partnership, except the assignee is not obligated for liabilities unknown to him at the time he became a limited partner and that could not be ascertained from the partnership agreement.

        NuStar Energy's operating subsidiaries conduct business or own assets in the United States, Canada, Mexico, the Netherland Antilles, the Netherlands and the United Kingdom. Maintenance of NuStar Energy's limited liability as a limited partner or member, respectively, of its operating subsidiaries, may require compliance with legal requirements in the jurisdictions in which the operating subsidiary conducts business. Limitations on the liability of limited partners or members for the obligations of a limited partner or member have not been clearly established in many jurisdictions. If it were determined that NuStar Energy was, by virtue of NuStar Energy's ownership interest in the operating subsidiaries or otherwise, conducting business in any state without compliance with the applicable limited partnership or limited liability company statute, or that the right or exercise of the right by the limited partners as a group to remove or replace NuStar Energy's general partner, to approve some amendments to the partnership agreement, or to take other action under the partnership agreement constituted "participation in the control" of NuStar Energy's business for purposes of the statutes of any relevant jurisdiction, then the limited partners could be held personally liable for NuStar Energy's obligations under the law of that jurisdiction to the same extent as the general partner under the circumstances. NuStar Energy will operate in a manner that the general partner considers reasonable and necessary or appropriate to preserve the limited liability of the limited partners.

Issuance of Additional Securities

        NuStar Energy's partnership agreement authorizes NuStar Energy to issue an unlimited number of additional limited partner interests and other equity securities for the consideration and on the terms and conditions established by the general partner in its sole discretion without the approval of any limited partners.

        It is possible that NuStar Energy will fund acquisitions through the issuance of additional common units or other equity securities. Holders of any additional common units NuStar Energy issues will be entitled to share equally with the then-existing holders of common units in NuStar Energy's distributions of available cash. In addition, the issuance of additional partnership interests may dilute the value of the interests of the then-existing holders of common units in NuStar Energy's net assets.

        There are no restrictions under the partnership agreement on the ability of the general partner to issue common units or common units junior or senior to the common units.

        In accordance with Delaware law and the provisions of the partnership agreement, NuStar Energy may also issue additional partnership securities that, in the sole discretion of the general partner, may have special voting rights to which the common units are not entitled.

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        Upon issuance of additional partnership securities, the general partner will be required to make additional capital contributions to the extent necessary to maintain its combined 2% general partner interest in NuStar Energy and NuStar Logistics. Moreover, the general partner will have the right, which it may from time to time assign in whole or in part to any of its affiliates, to purchase common units or other equity securities whenever, and on the same terms that NuStar Energy issues those securities to persons other than the general partner and its affiliates, to the extent necessary to maintain its percentage interest, including its interest represented by common units, that existed immediately prior to each issuance. The holders of common units will not have preemptive rights to acquire additional common units or other partnership interests.

Amendment of the Partnership Agreement

General

        Amendments to the partnership agreement may be proposed only by or with the consent of the general partner, which consent may be given or withheld in its sole discretion. In order to adopt a proposed amendment, other than the amendments discussed below, the general partner is required to seek written approval of the holders of the number of common units required to approve the amendment or call a meeting of the limited partners to consider and vote upon the proposed amendment. Except as described below, an amendment must be approved by a majority of the common units.

        We refer to the voting provision described above as a "unit majority."

Prohibited Amendments

        No amendment may be made that would:

•

enlarge the obligations of any limited partner without its consent, unless approved by at least a majority of the type or class of limited partner interests so affected;



•

enlarge the obligations of, restrict in any way any action by or rights of, or reduce in any way the amounts distributable, reimbursable or otherwise payable by NuStar Energy to the general partner or any of its affiliates without the consent of the general partner, which may be given or withheld in its sole discretion;



•

change the term of NuStar Energy;



•

provide that NuStar Energy is not dissolved upon an election to dissolve NuStar Energy by the general partner that is approved by the holders of a majority of the outstanding common units; or



•

give any person the right to dissolve NuStar Energy other than the general partner's right to dissolve NuStar Energy with the approval of the holders of a majority of the outstanding common units.

        The provision of the partnership agreement preventing the amendments having the effects described in the five bullets above can be amended upon the approval of the holders of at least 90% of the outstanding common units voting together as a single class.

No Unitholder Approval

        The general partner may generally make amendments to the partnership agreement without the approval of any limited partner or assignee to reflect:

•

a change in the name of NuStar Energy, the location of the principal place of business of NuStar Energy, the registered agent or the registered office of NuStar Energy;



•

the admission, substitution, withdrawal or removal of partners in accordance with the partnership agreement;

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•

a change that, in the sole discretion of the general partner, is necessary or advisable to qualify or continue the qualification of NuStar Energy as a limited partnership or a partnership in which the limited partners have limited liability under the laws of any state or to ensure that neither NuStar Energy nor NuStar Logistics will be treated as an association taxable as a corporation or otherwise taxed as an entity for federal income tax purposes;



•

an amendment that is necessary, in the opinion of counsel to NuStar Energy, to prevent NuStar Energy, the general partner, NuStar GP, LLC, or any of the directors, officers, agents or trustees of NuStar GP, LLC from in any manner being subjected to the provisions of the Investment Company Act of 1940, the Investment Advisors Act of 1940, or "plan asset" regulations adopted under ERISA, whether or not substantially similar to plan asset regulations currently applied or proposed;



•

subject to the limitations on the issuance of additional common units or other limited or general partner interests described above, an amendment that in the discretion of the general partner is necessary or advisable for the authorization of additional limited or general partner interests;



•

any amendment expressly permitted in the partnership agreement to be made by the general partner acting alone;



•

an amendment effected, necessitated or contemplated by a merger agreement that has been approved under the terms of the partnership agreement;



•

any amendment that, in the discretion of the general partner, is necessary or advisable for the formation by NuStar Energy of, or its investment in, any corporation, partnership or other entity, as otherwise permitted by the partnership agreement;



•

a change in the fiscal year or taxable year of NuStar Energy and related changes; and



•

any other amendments substantially similar to any of the matters described above.

        In addition, the general partner may make amendments to the partnership agreement without the approval of any limited partner or assignee if those amendments, in the discretion of the general partner:

•

do not adversely affect the limited partners (or any particular class of limited partners) in any material respect;



•

are necessary or advisable to satisfy any requirements, conditions or guidelines contained in any opinion, directive, order, ruling or regulation of any federal or state agency or judicial authority or contained in any federal or state statute;



•

are necessary or advisable to facilitate the trading of limited partner interests or to comply with any rule, regulation, guideline or requirement of any securities exchange on which the limited partner interests are or will be listed for trading, compliance with any of which the general partner deems to be in the best interests of NuStar Energy and the limited partners;



•

are necessary or advisable for any action taken by the general partner relating to splits or combinations of common units under the provisions of the partnership agreement; or



•

are required to effect the intent expressed in this prospectus or the intent of the provisions of the partnership agreement or are otherwise contemplated by the partnership agreement.

Opinion of Counsel and Unitholder Approval

        The general partner will not be required to obtain an opinion of counsel that an amendment will not result in a loss of limited liability to the limited partners or result in NuStar Energy being treated as an entity for federal income tax purposes if one of the amendments described above under "—Amendment of the Partnership Agreement" should occur. No other amendments to the partnership agreement will become effective without the approval of holders of at least 90% of the common units unless NuStar Energy obtains an opinion of counsel to the effect that the amendment will not affect

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the limited liability under applicable law of any limited partner in NuStar Energy or cause NuStar Energy or its operating subsidiaries to be taxable as a corporation or otherwise to be taxed as an entity for federal income tax purposes (to the extent not previously taxed as such).

        Any amendment that would have a material adverse effect on the rights or preferences of any type or class of outstanding common units in relation to other classes of common units will require the approval of at least a majority of the type or class of common units so affected. Any amendment that reduces the voting percentage required to take any action is required to be approved by the affirmative vote of limited partners constituting not less than the voting requirement sought to be reduced.

Merger/Consolidation

        A merger or consolidation of NuStar Energy requires the prior approval of NuStar Energy's general partner. The general partner must also approve the merger agreement, which must include certain information as set forth in NuStar Energy's partnership agreement. Once approved by the general partner, the merger agreement must be submitted to a vote of NuStar Energy's limited partners, and the merger agreement will be approved upon receipt of the affirmative vote or consent of the holders of a unit majority (unless the affirmative vote of the holders of a greater percentage is required under the merger agreement or Delaware law).

        Unit Majority.    A unit majority consists of at least a majority of the outstanding common units.

Disposal of Assets

        Except in connection with a dissolution and liquidation of the partnership or a duly approved merger, NuStar Energy's general partner may not (a) sell, exchange or otherwise dispose of all or substantially all of NuStar Energy's assets in a single transaction or a series of related transactions, or (b) approve on behalf of the partnership the sale, exchange or other disposition of all or substantially all of the assets of the operating partnership without the approval of the holders of a unit majority. However, the general partner may mortgage, pledge, hypothecate or grant a security interest in all or substantially all of the assets of the partnership or operating partnership without the approval of the unitholders. In addition, the general partner may sell any or all of the assets of the partnership or operating partnership in a forced sale pursuant to the foreclosure of, or other realization upon, any such encumbrance without the approval of the unitholders.

Termination and Dissolution

        NuStar Energy will continue in existence as a limited partnership until terminated under its partnership agreement. NuStar Energy will dissolve upon:

•

the election of the general partner to dissolve NuStar Energy, if approved by the holders of common units representing a unit majority;



•

the sale, exchange or other disposition of all or substantially all of the assets and properties of NuStar Energy;



•

the entry of a decree of judicial dissolution of NuStar Energy; or



•

the withdrawal or removal of the general partner or any other event that results in its ceasing to be the general partner other than by reason of a transfer of its general partner interest in accordance with the partnership agreement or withdrawal or removal following approval and admission of a successor.

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        Upon a dissolution under the last clause above, the holders of common units representing a unit majority may also elect, within specific time limitations, to reconstitute NuStar Energy and continue its business on the same terms and conditions described in the partnership agreement by forming a new limited partnership on terms identical to those in the partnership agreement and having as general partner an entity approved by the holders of common units representing a unit majority, subject to receipt by NuStar Energy of an opinion of counsel to the effect that:

•

the action would not result in the loss of limited liability of any limited partner; and



•

neither NuStar Energy, the reconstituted limited partnership, nor any operating subsidiary would be treated as an association taxable as a corporation or otherwise be taxable as an entity for federal income tax purposes upon the exercise of that right to continue.

Liquidation and Distribution of Proceeds

        Upon its dissolution, unless NuStar Energy is reconstituted and continued as a new limited partnership, the liquidator authorized to wind up NuStar Energy's affairs will, acting with all of the powers of the general partner that the liquidator deems necessary or desirable in its judgment, liquidate NuStar Energy's assets and apply the proceeds of the liquidation as provided in "Cash Distribution Policy of NuStar Energy—Distributions of Cash upon Liquidation." The liquidator may defer liquidation or distribution of NuStar Energy's assets for a reasonable period of time or distribute assets to partners in kind if it determines that a sale would be impractical or would cause undue loss to the partners.

Withdrawal or Removal of the General Partner

        Except as described below, NuStar Energy's general partner has agreed not to withdraw voluntarily as general partner of NuStar Energy or as the general partner of any operating subsidiary prior to March 31, 2011 without obtaining the approval of the holders of at least a majority of the outstanding common units, excluding common units held by the general partner and its affiliates, and furnishing an opinion of counsel regarding limited liability and tax matters. On or after March 31, 2011, NuStar Energy's general partner may withdraw as general partner without first obtaining approval of any unitholder by giving 90 days' written notice, and that withdrawal will not constitute a violation of the partnership agreement. Notwithstanding the information above, NuStar Energy's general partner may withdraw without unitholder approval upon 90 days' notice to the limited partners if at least 50% of the outstanding common units are held or controlled by one person and its affiliates other than the general partner and its affiliates. In addition, the partnership agreement permits the general partner in some instances to sell or otherwise transfer all of its general partner interest in NuStar Energy without the approval of the unitholders. Please read "—Transfer of General Partner Interests."

        Upon the withdrawal of the general partner under any circumstances, other than as a result of a transfer of all or a part of its general partner interest in NuStar Energy, the holders of common units representing a unit majority may select a successor to that withdrawing general partner. If a successor is not elected, or is elected but an opinion of counsel regarding limited liability and tax matters cannot be obtained, NuStar Energy will be dissolved, wound up and liquidated, unless within 180 days after that withdrawal, the holders of a majority of the outstanding common units agree in writing to continue the business of NuStar Energy and to appoint a successor general partner. Please read "—Termination and Dissolution."

        If the general partner withdraws under circumstances where such withdrawal does not violate the partnership agreement, and a successor general partner is elected under the terms of the partnership agreement, the departing general partner will have the option to require the successor general partner to purchase its general partner interests and incentive distribution rights for cash. If the general partner withdraws under circumstances where such withdrawal does violate the partnership agreement, and a successor general partner is elected, the successor general partner will have the option to purchase the general partner interests and incentive distribution rights of the departing general partner. If such general partner interests and incentive distribution rights are not purchased by the successor general partner, they will be converted into common units.

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        The general partner may not be removed unless that removal is approved by the vote of the holders of not less than a majority of the outstanding common units, and NuStar Energy receives an opinion of counsel regarding limited liability and tax matters. Any removal of the general partner is also subject to the approval of a successor general partner by the vote of the holders of a majority of the outstanding common units.

        If the general partner is removed under circumstances where cause does not exist, and a successor general partner is elected under the partnership agreement, the departing general partner will have the option to require the successor general partner to purchase its general partner interests and incentive distribution rights for cash. If the general partner is removed under circumstances where cause does exist, and a successor general partner is elected, the successor general partner will have the option to purchase the general partner interests and incentive distribution rights of the departing general partner. If the general partner interests and incentive distribution rights are not purchased by the successor general partner, they will be converted into common units.

        "Cause" is narrowly defined to mean that a court of competent jurisdiction has entered a final, non-appealable judgment finding the general partner liable for actual fraud, gross negligence, or willful or wanton misconduct in its capacity as the general partner.

        Withdrawal or removal of the general partner of NuStar Energy also constitutes withdrawal or removal of the general partner of NuStar Logistics.

        In addition, NuStar Energy will be required to reimburse the departing general partner for all amounts due the departing general partner, including, without limitation, all employee-related liabilities, including severance liabilities, incurred for the termination of any employees employed by the departing general partner for the benefit of NuStar Energy.

Transfer of General Partner Interests

        Prior to March 31, 2011, NuStar Energy's general partner may not transfer all or any part of its general partner interest unless such transfer (a) has been approved by the prior written consent or vote of the holders of at least a majority of the outstanding common units (excluding any common units held by the general partner or its affiliates) or (b) is of all, but not less than all, of its general partner interest to (i) an affiliate of the general partner or (ii) another person in connection with the merger or consolidation of the general partner with or into such person or the transfer by the general partner of all or substantially all of its assets to such person.

        On or after March 31, 2011, NuStar Energy's general partner may transfer all or any part of its general partner interest in NuStar Energy without unitholder approval.

        No transfer by NuStar Energy's general partner of all or any part of its general partner interest is permitted unless (a) the transferee agrees to assume the rights and duties of the general partner and be bound by the partnership agreement and (b) the partnership receives an opinion of counsel regarding limited liability and tax matters.

Change of Management Provisions

        NuStar Energy's partnership agreement contains specific provisions that are intended to discourage a person or group from attempting to remove the general partner or otherwise change management, including the following:

•

Any units held by a person that owns 20% or more of any class of units then outstanding, other than the general partner and its affiliates, cannot be voted on any matter.



•

The partnership agreement contains provisions limiting the ability of unitholders to call meetings or to acquire information about the partnership's operations, as well as other provisions limiting the unitholders' ability to influence the manner or direction of management.

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Limited Call Right

        If at any time NuStar Energy's general partner and its affiliates own 80% or more of the issued and outstanding limited partner interests of any class, the general partner will have the right (which right it may assign and transfer to the partnership or any affiliate of the general partner) to purchase all, but not less than all, of the outstanding limited partner interests of that class that are held by non-affiliated persons. The record date for determining ownership of the limited partner interests to be purchased by the general partner will be selected by the general partner, and the general partner must mail notice of its election to purchase the interests to the holders of such interests at least 10 but not more than 60 days prior to the purchase date. The purchase price in the event of a purchase under these provisions would be the greater of (a) the current market price (as defined in the partnership agreement) of the limited partner interests of that class as of the date three days prior to the date the general partner mails notice of its election to purchase the interests and (b) the highest price paid by the general partner or any of its affiliates for any limited partner interest of that class purchased within the 90 days preceding the date the general partner mails notice of its election to purchase the interests.

Meetings; Voting

        Special meetings of NuStar Energy's limited partners may be called by the general partner or by limited partners owning 20% or more of the outstanding limited partner interests of the class or classes for which a meeting is proposed. The general partner must send notice of any meeting to the limited partners, and a meeting may not be held less than 10 days nor more than 60 days after the mailing of the notice. For the purpose of determining the limited partners entitled to notice of, and to vote at, a meeting of the limited partners (or to give written approvals without a meeting as described below), the general partner will set a record date, which may not be less than 10 nor more than 60 days before the date of the meeting (or the date by which the limited partners are requested to submit written approvals). Only record holders of limited partner interests on such record date are entitled to notice of, and to vote at, a meeting of the limited partners (or to vote on any action to be taken without a meeting).

        If authorized by the general partner, any action that may be taken at a meeting of limited partners may be taken without a meeting by obtaining approval in writing of the necessary percentage of the limited partners that would be required to authorize or take the action at a meeting of the limited partners.

        Each record holder of a limited partner interest has a vote according to his percentage interest in the partnership. Limited partner interests held for a person's account by another person (such as a broker, dealer, or bank), in whose name such limited partner interests are registered, will be voted by such other person in favor of, and at the direction of, the beneficial owner unless the arrangement between such persons provides otherwise. Representation in person or by proxy of a majority of the outstanding limited partner interests of the class or classes for which a meeting has been called will constitute a quorum at such meeting (unless a particular action by the limited partners requires approval by a greater percentage of limited partner interests, in which case the quorum shall be such greater percentage). At any meeting at which a quorum is present, the act of the limited partners holding a majority of the outstanding limited partner interests entitled to vote at the meeting will be deemed to be the act of all the limited partners, unless a greater or different percentage is required under the partnership agreement, in which case the act of the limited partners holding such greater or different percentage of the outstanding limited partner interests will be required.

        NuStar Energy unitholders have no right to elect NuStar Energy's general partner on an annual or other continuing basis. NuStar Energy's partnership agreement explicitly authorizes the general partner to issue limited partner interests having special or superior voting rights without the consent of the limited partners.

Transfer of Units and Status as a Limited Partner or Assignee

        No transfer of NuStar Energy limited partner interests will be recognized by the partnership unless certificate(s) representing those limited partnership interests are surrendered and such certificates are accompanied by a duly executed transfer application. Each transferee of NuStar Energy limited partner interests must execute a transfer application whereby the transferee, among other things, requests

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admission as a substituted limited partner, makes certain representations, executes and agrees to comply with and be bound by the partnership agreement, and gives the consents and approvals and makes the waivers contained in the partnership agreement. Transferees may hold common units in nominee accounts.

        Once a transferee has executed and delivered a transfer application in accordance with the partnership agreement, the transferee becomes an assignee. An assignee becomes a limited partner upon the consent of the general partner and the recordation of the name of the assignee on NuStar Energy's books and records. Such consent may be withheld in the sole discretion of the general partner. An assignee, pending its admission as a substituted limited partner, is entitled to an interest in NuStar Energy equivalent to that of a limited partner with respect to the right to share in allocations and distributions, including liquidating distributions. NuStar Energy's general partner will vote and exercise, at the written direction of the assignee, other powers attributable to limited partner interests owned by an assignee who has not become a substituted limited partner.

        Transferees who do not execute and deliver transfer applications will be treated neither as assignees nor as record holders of limited partner interests and will not receive distributions, federal income tax allocations or reports furnished to record holders of limited partner interests. The only right such transferees will have is the right to admission as a substituted limited partner upon execution of a transfer application, subject to the approval of the general partner. A nominee or broker who has executed a transfer application with respect to limited partner interests held in street name or nominee accounts will receive distributions and reports pertaining to such limited partner interests.

Non-Citizen Assignees; Redemption

        If NuStar Energy is or becomes subject to federal, state or local laws or regulations that, in the reasonable determination of the general partner, create a substantial risk of cancellation or forfeiture of any property that NuStar Energy has an interest in because of the nationality, citizenship or other related status of any limited partner or assignee, NuStar Energy may redeem the common units held by the limited partner or assignee at their current market price. In order to avoid any cancellation or forfeiture, the general partner may require each limited partner or assignee to furnish information about his nationality, citizenship or related status. If a limited partner or assignee fails to furnish information about this nationality, citizenship or other related status within 30 days after a request for the information or the general partner determines after receipt of the information that the limited partner or assignee is not an eligible citizen, the limited partner or assignee may be treated as a non-citizen assignee. In addition to other limitations on the rights of an assignee who is not a substituted limited partner, a non-citizen assignee does not have the right to direct the voting of his common units and may not receive distributions in kind upon NuStar Energy's liquidation.

Indemnification

        Under the partnership agreement, in most circumstances, NuStar Energy will indemnify the following persons, to the fullest extent permitted by law, from and against all losses, claims, damages or similar events:

•

the general partner;



•

any departing general partner;



•

any person who is or was an affiliate of the general partner or any departing general partner;



•

any person who is or was a partner, officer, director, employee, agent, or trustee of the general partner, NuStar GP, LLC, or departing general partner or any affiliate of the general partner, NuStar GP, LLC, or departing general partner; or



•

any person who is or was serving at the request of the general partner or departing general partner or any affiliate of the general partner or departing general partner as an officer, director, employee, member, partner, agent, or trustee of another person.

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        Any indemnification under these provisions will only be out of NuStar Energy's assets. Unless it otherwise agrees in its sole discretion, the general partner shall not be personally liable for any of NuStar Energy's indemnification obligations, nor have any obligation to contribute or loan funds or assets to NuStar Energy to enable NuStar Energy to effectuate indemnification. NuStar Energy is authorized to purchase insurance against liabilities asserted against and expenses incurred by persons for its activities, regardless of whether NuStar Energy would have the power to indemnify the person against liabilities under the partnership agreement.

Books and Reports

        The general partner is required to keep appropriate books of NuStar Energy's business at NuStar Energy's principal offices. The books will be maintained for both tax and financial reporting purposes on an accrual basis. For tax and financial reporting purposes, NuStar Energy's fiscal year is the calendar year.

        NuStar Energy will furnish or make available to record holders of common units, within 120 days after the close of each fiscal year, an annual report containing audited financial statements and a report on those financial statements by its registered public accounting firm. Except for its fourth quarter, NuStar Energy will also furnish or make available summary financial information within 90 days after the close of each quarter.

        NuStar Energy will furnish each record holder of a unit with information reasonably required for tax reporting purposes within 90 days after the close of each calendar year. This information is expected to be furnished in summary form so that some complex calculations normally required of partners can be avoided. NuStar Energy's ability to furnish this summary information to unitholders will depend on the cooperation of unitholders in supplying it with specific information. Every unitholder will receive information to assist him in determining his federal and state tax liability and filing his federal and state income tax returns, regardless of whether he supplies NuStar Energy with information.

Right to Inspect NuStar Energy's Books and Records

        The partnership agreement provides that a limited partner can, for a purpose reasonably related to his interest as a limited partner, upon reasonable demand and at his own expense, have furnished to him:

•

a current list of the name and last known address of each partner;



•

a copy of NuStar Energy's tax returns;



•

information as to the amount of cash, and a description and statement of the agreed value of any other property or services, contributed or to be contributed by each partner and the date on which each became a partner;



•

copies of the partnership agreement, the certificate of limited partnership of the partnership, related amendments and powers of attorney under which they have been executed;



•

information regarding the status of NuStar Energy's business and financial condition; and



•

any other information regarding NuStar Energy's affairs as is just and reasonable.

        The general partner may, and intends to, keep confidential from the limited partners trade secrets or other information the disclosure of which the general partner believes in good faith is not in NuStar Energy's best interests or which NuStar Energy is required by law or by agreements with third parties to keep confidential.

Registration Rights

        Under the partnership agreement, NuStar Energy has agreed to register for resale under the Securities Act of 1933, as amended, and applicable state securities laws any common units or other partnership securities proposed to be sold by the general partner or any of its affiliates or their assignees if an exemption from the registration requirements is not otherwise available. These registration rights continue for two years following any withdrawal or removal of Riverwalk Logistics, L.P. as the general partner of NuStar Energy. NuStar Energy is obligated to pay all expenses incidental to the registration, excluding underwriting discounts and commissions.

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CONFLICTS OF INTEREST AND FIDUCIARY RESPONSIBILITIES

Conflicts of Interest

        Riverwalk Logistics, L.P., the general partner of NuStar Energy, has a legal duty to manage NuStar Energy in a manner beneficial to NuStar Energy's unitholders. This legal duty originates in statutes and judicial decisions and is commonly referred to as a "fiduciary" duty. However, because Riverwalk Logistics is indirectly owned by NuStar GP Holdings, LLC ("NuStar GP Holdings"), the officers and directors of Riverwalk Logistics' general partner, NuStar GP, LLC, also have fiduciary duties to manage the business of Riverwalk Logistics in a manner beneficial to NuStar GP Holdings and its public unitholders. As a result of this relationship, conflicts of interest may arise between NuStar Energy's general partner and its affiliates, including NuStar GP Holdings' public unitholders, on the one hand, and NuStar Energy and its limited partners, including the public unitholders, on the other hand.

        NuStar Energy's partnership agreement contains provisions that allow the general partner to take into account the interests of parties in addition to NuStar Energy in resolving conflicts of interest. In effect, these provisions limit the general partner's fiduciary duties to the unitholders. The partnership agreement also restricts the remedies available to unitholders for actions taken that might, without those limitations, constitute breaches of fiduciary duty. Whenever a conflict arises between the general partner or its affiliates, on the one hand, and NuStar Energy or any other partner, on the other hand, the general partner will resolve that conflict.

Resolution of Conflicts of Interest

        The general partner will not be in breach of its obligations under the partnership agreement or its duties to NuStar Energy or the unitholders if the resolution of the conflict is considered to be fair and reasonable to NuStar Energy. Any resolution is considered to be fair and reasonable to NuStar Energy if that resolution is:

•

approved by a conflicts committee consisting of three independent directors of NuStar GP, LLC, although no party is obligated to seek approval and the general partner may adopt a resolution or course of action that has not received approval;



•

on terms no less favorable to NuStar Energy than those generally being provided to or available from unrelated third parties; or



•

fair to NuStar Energy, taking into account the totality of the relationships between the parties involved, including other transactions that may be particularly favorable or advantageous to NuStar Energy.

        In resolving a conflict, the general partner may, unless the resolution is specifically provided for in the partnership agreement, consider:

•

the relative interests of the parties involved in the conflict or affected by the action;



•

any customary or accepted industry practices or historical dealings with a particular person or entity; and



•

generally accepted accounting principles and other factors it considers relevant, if applicable.

        Conflicts of interest could arise in the situations described below, among others.

Actions taken by the general partner may affect the amount of cash available for distribution to unitholders or accelerate the right to convert subordinated units.

        The amount of cash that is available for distribution to unitholders is affected by decisions of the general partner regarding:

•

amount and timing of asset purchases and sales;



•

cash expenditures;

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•

borrowings;



•

issuance of additional units; and



•

the creation, decrease or increase of reserves in any quarter.

        In addition, borrowings by NuStar Energy do not constitute a breach of any duty owed by the general partner to the unitholders, including borrowings that have the purpose or effect of enabling the general partner to receive distributions or the incentive distribution rights.

        The partnership agreement provides that NuStar Energy may borrow funds from the general partner and its affiliates. The general partner and its affiliates may not borrow funds from NuStar Energy.

We do not have any employees and rely on the employees of the general partner and its affiliates.

        We do not have any officers or employees and rely solely on officers and employees of NuStar GP, LLC, and its affiliates. Affiliates of the general partner may conduct businesses and activities of their own in which we have no economic interest. In the future, if these separate activities were significantly greater than our activities, there could be material competition for the time and effort of the officers and employees who provide services to the general partner and NuStar GP, LLC.

We reimburse NuStar GP LLC for expenses and costs incurred on our behalf.

        Under NuStar Energy's partnership agreement, we reimburse NuStar Energy's general partner and its affiliates for costs incurred in managing and operating NuStar Energy and its subsidiaries. The partnership agreement provides that the general partner will determine the expenses that are allocable to it in any reasonable manner determined by the general partner in its sole discretion.

The general partner intends to limit its liability regarding NuStar Energy's obligations.

        The general partner intends to limit its liability under contractual arrangements so that the other party has recourse only to all or particular assets of NuStar Energy, and not against the general partner or its assets. NuStar Energy's partnership agreement provides that any action taken by the general partner to limit its liability is not a breach of the general partner's fiduciary duties, even if we could have obtained more favorable terms without the limitation on liability.

Common unitholders will have no right to enforce obligations of the general partner and its affiliates under agreements with NuStar Energy.

        Any agreements between NuStar Energy on the one hand, and the general partner and its affiliates, on the other, will not grant to the unitholders, separate and apart from NuStar Energy, the right to enforce the obligations of the general partner and its affiliates in favor of NuStar Energy. Therefore, the general partner, in its capacity as the general partner of NuStar Energy, will be primarily responsible for enforcing these obligations.

Contracts between NuStar Energy, on the one hand, and the general partner and its affiliates, on the other, are not the result of arm's-length negotiations.

        Neither the NuStar Energy partnership agreement nor any of the other agreements, contracts and arrangements between NuStar Energy, on the one hand, and the general partner and its affiliates, on the other, are or will be the result of arm's-length negotiations.

Common units are subject to the general partner's limited call right.

        The general partner may exercise its right to call and purchase common units as provided in NuStar Energy's partnership agreement or assign this right to one of its affiliates or to us. The general partner may use its own discretion, free of fiduciary duty restrictions, in determining whether to

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exercise this right. As a consequence, a common unitholder may have his common units purchased from him at an undesirable time or price.

NuStar GP Holdings may compete with NuStar Energy.

        NuStar Energy entered into a Non-Compete Agreement with NuStar GP Holdings on July 19, 2006. Under the Non-Compete Agreement, NuStar GP Holdings has a right of first refusal with respect to the potential acquisition of general partner and other equity interests in publicly traded partnerships under common ownership with the general partner interest. NuStar Energy has a right of first refusal with respect to the potential acquisition of assets that relate to the transportation, storage or terminalling of crude oil, feedstocks or refined petroleum products (including petrochemicals) in the United States and internationally. With respect to any other business opportunities, neither NuStar Energy nor NuStar GP Holdings are prohibited from engaging in any business, even if NuStar Energy and NuStar GP Holdings would have a conflict of interest with respect to such other business opportunity.

Fiduciary duties owed to unitholders by the general partner are prescribed by law and NuStar Energy's partnership agreement.

        The general partner is accountable to NuStar Energy and its unitholders as a fiduciary. These limited fiduciary duties are very different from the more familiar duties of a corporate board of directors, which must always act in the best interests of the corporation and its stockholders.

Fiduciary Duties

        Fiduciary duties are generally considered to include an obligation to act with due care and loyalty. The duty of care, in the absence of a provision in a partnership agreement providing otherwise, generally requires a general partner to act for the partnership in the same manner as a prudent person would act on his own behalf. The duty of loyalty, in the absence of a provision in a partnership agreement providing otherwise, generally prohibits a general partner from taking any action or engaging in any transaction where a conflict of interest is present. The Delaware Revised Uniform Limited Partnership Act (referred to herein as the Delaware Act) generally provides that a limited partner may institute legal action on a partnership's behalf to recover damages from a third party where a general partner has refused to institute the action or where an effort to cause a general partner to do so is not likely to succeed. In addition, the statutory or case law of some jurisdictions may permit a limited partner to institute legal action on behalf of himself and all other similarly situated limited partners to recover damages from a general partner for violations of its fiduciary duties to the limited partners.

        The Delaware Act provides that Delaware limited partnerships may, in their partnership agreements, restrict or expand the fiduciary duties owed by a general partner to limited partners and the partnership.

        Fiduciary standards may be modified by the NuStar Energy partnership agreement. NuStar Energy's partnership agreement contains various provisions restricting the fiduciary duties that might otherwise be owed by the general partner. The following is a summary of the material restrictions of the fiduciary duties owed by the general partner to the limited partners:

        The partnership agreement contains provisions that waive or consent to conduct by the general partner and its affiliates that might otherwise raise issues as to compliance with fiduciary duties or applicable law. For example, the partnership agreement permits the general partner to make a number of decisions in its "sole discretion," such as:

•

the incurrence of indebtedness;



•

the acquisition or disposition of assets, except for the disposition of all of the assets of the partnership which requires unitholder approval;

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•

the negotiation of any contracts;



•

the disposition of partnership cash; and



•

the purchase or disposition of partnership securities, other than issuance of securities senior to the common units.

        Sole discretion entitles the general partner to consider only the interests and factors that it desires and it does not have a duty or obligation to give any consideration to any interest of, or factors affecting, NuStar Energy, its affiliates or any limited partner, including the public unitholders. Other provisions of NuStar Energy's partnership agreement provide that the general partner's actions must be carried out in its reasonable discretion.

        The partnership agreement generally provides that affiliated transactions and resolutions of conflicts of interest not involving a required vote of unitholders must be "fair and reasonable" to NuStar Energy under the factors previously set forth. In determining whether a transaction or resolution is "fair and reasonable" the general partner may consider interests of all parties involved, including its own. Unless the general partner has acted in bad faith, the action taken by the general partner will not constitute a breach of its fiduciary duty.

        In addition to the other more specific provisions limiting the obligations of the general partner, the partnership agreement further provides that the general partner and the officers and directors of NuStar GP, LLC will not be liable for monetary damages to NuStar Energy, the limited partners or assignees for errors of judgment or for any acts or omissions if the general partner and those other persons acted in good faith.

        NuStar Energy is required to indemnify the general partner and NuStar GP, LLC and their officers, directors, employees, affiliates, partners, members, agents and trustees, to the fullest extent permitted by law, against liabilities, costs and expenses incurred by the general partner and NuStar GP, LLC or these other persons. This indemnification is required if the general partner or these persons acted in good faith and in a manner they reasonably believed to be in, or (in the case of a person other than the general partner) not opposed to, the best interests of NuStar Energy. Indemnification is required for criminal proceedings if the general partner and NuStar GP, LLC or these other persons had no reasonable cause to believe their conduct was unlawful. Thus, the general partner and NuStar GP, LLC could be indemnified for their negligent acts if they met these requirements concerning good faith and the best interests of NuStar Energy.

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DESCRIPTION OF NUSTAR LOGISTICS DEBT SECURITIES

        The following description sets forth the general terms and provisions that apply to the debt securities that may be offered by NuStar Logistics. Each prospectus supplement will state the particular terms that will apply to the debt securities included in the supplement.

        The NuStar Logistics debt securities will be either senior debt securities or subordinated debt securities of NuStar Logistics. All debt securities will be unsecured. The NuStar Logistics senior debt securities will have the same rank as all of NuStar Logistics' and NPOP's other unsecured and unsubordinated debt. The subordinated debt securities will be subordinated to senior indebtedness as described under "Provisions Only in the Subordinated Indenture—Subordinated Debt Securities Subordinated to Senior Debt" below.

        If NuStar Logistics offers senior debt securities, it will issue them under the senior indenture among NuStar Logistics, NuStar Energy, as guarantor, and Wells Fargo Bank, National Association (as successor-in-interest to The Bank of New York), as trustee, dated as of July 15, 2002, as supplemented by a supplemental indenture. If NuStar Logistics offers subordinated debt securities, it will issue them under a subordinated indenture among NuStar Logistics, NuStar Energy, as guarantor, and the trustee. The senior indenture and a form of the subordinated indenture have been filed as exhibits to the registration statement of which this prospectus is a part.

        Neither indenture limits the aggregate principal amount of debt securities that NuStar Logistics may issue under that indenture. The debt securities may be issued in one or more series as NuStar Logistics may authorize from time to time. You should read the indentures for provisions that may be important to you because the indentures, and not this description, govern your rights as a holder of debt securities.

Guarantees

        NuStar Logistics' payment obligations under any series of debt securities will be fully and unconditionally guaranteed by NuStar Energy and NPOP, jointly and severally. Each of NuStar Energy and NPOP will execute a notation of guarantee as further evidence of its guarantee. The applicable prospectus supplement will describe the terms of any guarantees by NuStar Energy and NPOP.

        Pursuant to the guarantees, each of NuStar Energy and NPOP will guarantee the due and punctual payment of the principal of, and interest and premium, if any, on, the debt securities of a particular series, when the same shall become due, whether by acceleration or otherwise. The guarantees will be enforceable against each of NuStar Energy and NPOP without any need to first enforce any debt securities against NuStar Logistics.

        The guarantees of the senior debt securities:

•

will be the unsecured and unsubordinated general obligations of NuStar Energy and NPOP; and



•

will rank on a parity with all of the other unsecured and unsubordinated indebtedness of NuStar Energy and NPOP.

        If a series of subordinated debt securities is guaranteed by NuStar Energy and NPOP, then the guarantees will be subordinated to the senior debt of NuStar Energy and NPOP, respectively, to substantially the same extent as the series of subordinated debt securities is subordinated to the senior debt of NuStar Logistics.

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Specific Terms of Each Series of NuStar Logistics Debt Securities in the Prospectus Supplement

        NuStar Logistics will prepare a prospectus supplement and a supplemental indenture or authorizing resolutions relating to any series of debt securities being offered, which will include specific terms relating to such debt securities. These terms will include some or all of the following:

•

the form and title of the debt securities;



•

the total principal amount of the debt securities;



•

the date or dates on which the debt securities may be issued;



•

whether the debt securities are senior or subordinated debt securities;



•

the currency or currencies in which principal and interest will be paid, if not U.S. dollars;



•

the portion of the principal amount which will be payable if the maturity of the debt securities is accelerated;



•

any right NuStar Logistics may have to defer payments of interest by extending the dates payments are due and whether interest on those deferred amounts will be payable as well;



•

the dates on which the principal of the debt securities will be payable;



•

the interest rate that the debt securities will bear and the interest payment dates for the debt securities;



•

any conversion or exchange provisions;



•

any optional redemption provisions;



•

any sinking fund or other provisions that would obligate NuStar Logistics to repurchase or otherwise redeem the debt securities;



•

any changes to or additional events of default or covenants;



•

the subordination, if any, of the debt securities and any changes to the subordination provisions of the subordinated indenture; and



•

any other terms of the debt securities.

Provisions only in the NuStar Logistics Senior Indenture

Summary

        The NuStar Logistics senior debt securities will rank equally in right of payment with all other senior and unsubordinated debt of NuStar Logistics and NPOP and senior in right of payment to any subordinated debt (including the subordinated debt securities) of NuStar Logistics and NPOP. The senior indenture contains restrictive covenants, including provisions that:

•

limit the ability of NuStar Logistics to put liens on any of its property or assets; and



•

limit the ability of NuStar Logistics to sell and lease back its principal assets.

        Subordinated debt securities issued by NuStar Logistics under the subordinated indenture may or may not be subject to similar provisions, as will be specified in the applicable prospectus supplement. NuStar Logistics has described below these provisions and some of the defined terms used in them.

Limitation on Liens

        The senior indenture provides that NuStar Logistics will not, nor will it permit any subsidiary to, create, assume, incur or suffer to exist any lien upon any property or assets, whether owned or leased on the date of the senior indenture or thereafter acquired, to secure any of its debt or debt of any other person (other than the senior debt securities issued thereunder), without in any such case making effective provision whereby all of the senior debt securities outstanding thereunder shall be secured equally and ratably with, or prior to, such debt so long as such debt shall be so secured.

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        This restriction does not apply to:

(1)

Permitted Liens, as defined below;



(2)

any lien upon any property or assets of NuStar Logistics or any subsidiary in existence on the date the senior debt securities of such series are first issued or created pursuant to an "after-acquired property" clause or similar term or provided for pursuant to agreements existing on such date;



(3)

any lien upon any property or assets created at the time of acquisition of such property or assets by NuStar Logistics or any subsidiary or within one year after such time to secure all or a portion of the purchase price for such property or assets or debt incurred to finance such purchase price, whether such debt was incurred prior to, at the time of or within one year after the date of such acquisition;



(4)

any lien upon any property or assets existing thereon at the time of the acquisition thereof by NuStar Logistics or any subsidiary; provided, however, that such lien only encumbers the property or assets so acquired;



(5)

any lien upon any property or assets of a person existing thereon at the time such person becomes a subsidiary by acquisition, merger or otherwise; provided, however, that such lien only encumbers the property or assets of such person at the time such person becomes a subsidiary;



(6)

any lien upon any property or assets to secure all or part of the cost of construction, development, repair or improvements thereon or to secure debt incurred prior to, at the time of, or within one year after completion of such construction, development, repair or improvements or the commencement of full operations thereof, whichever is later, to provide funds for any such purpose;



(7)

any lien imposed by law or order as a result of any proceeding before any court or regulatory body that is being contested in good faith, and liens which secure a judgment or other court-ordered award or settlement as to which NuStar Logistics or the applicable subsidiary has not exhausted its appellate rights;



(8)

any lien upon any additions, improvements, replacements, repairs, fixtures, appurtenances or component parts thereof attaching to or required to be attached to property or assets pursuant to the terms of any mortgage, pledge agreement, security agreement or other similar instrument creating a lien upon such property or assets permitted by clauses (1) through (7) above;



(9)

any extension, renewal, refinancing, refunding or replacement (or successive extensions, renewals, refinancings, refundings or replacements) of any lien, in whole or in part, referred to in clauses (1) through (8), inclusive, above; provided, however, that the principal amount of debt secured thereby shall not exceed the principal amount of debt so secured at the time of such extension, renewal, refinancing, refunding or replacement (plus in each case the aggregate amount of premiums, other payments, costs and expenses required to be paid or incurred in connection with such extension, renewal, refinancing, refunding or replacement); provided, further, however, that such extension, renewal, refinancing, refunding or replacement lien shall be limited to all or a part of the property (including improvements, alterations and repairs on such property) subject to the encumbrance so extended, renewed, refinanced, refunded or replaced (plus improvements, alterations and repairs on such property); or



(10)

any lien resulting from the deposit of moneys or evidence of indebtedness in trust for the purpose of defeasing debt of NuStar Logistics or any subsidiary.

        Notwithstanding the foregoing, NuStar Logistics may, and may permit any subsidiary to, create, assume, incur, or suffer to exist any lien upon any property or assets to secure its debt or debt of any person (other than the senior debt securities) that is not excepted by clauses (1) through (10),

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inclusive, above without securing the senior debt securities issued under the senior indenture, provided that the aggregate principal amount of all debt then outstanding secured by such lien and all similar liens, together with all Attributable Indebtedness, as defined below, from Sale-Leaseback Transactions, as defined below (excluding Sale-Leaseback Transactions permitted by clauses (1) through (4), inclusive, of the first paragraph of the restriction on sale-leasebacks covenant described below) does not exceed 10% of Consolidated Net Tangible Assets (as defined below).

        "Permitted Liens" means:

•

Liens upon rights-of-way for pipeline purposes created by a person other than NuStar Logistics;



•

any statutory or governmental lien or lien arising by operation of law, or any mechanics', repairmen's, materialmen's, suppliers', carriers', landlords', warehousemen's or similar lien incurred in the ordinary course of business which is not yet due or which is being contested in good faith by appropriate proceedings and any undetermined lien which is incidental to construction, development, improvement or repair;



•

the right reserved to, or vested in, any municipality or public authority by the terms of any right, power, franchise, grant, license, permit or by any provision of law, to purchase or recapture or to designate a purchaser of, any property;



•

any lien of taxes and assessments which are (A) for the then current year, (B) not at the time delinquent, or (C) delinquent but the validity of which is being contested in good faith at the time by NuStar Logistics or any subsidiary;



•

any lien of, or to secure the performance of, leases, other than capital leases;



•

any lien upon, or deposits of, any assets in favor of any surety company or clerk of court for the purpose of obtaining indemnity or stay of judicial proceedings;



•

any lien upon property or assets acquired or sold by NuStar Logistics or any subsidiary resulting from the exercise of any rights arising out of defaults on receivables;



•

any lien incurred in the ordinary course of business in connection with worker's compensation, unemployment insurance, temporary disability, social security, retiree health or similar laws or regulations or to secure obligations imposed by statute or governmental regulations;



•

any lien in favor of NuStar Logistics or any subsidiary;



•

any lien in favor of the United States of America or any state thereof, or any department, agency or instrumentality or political subdivision of the United States of America or any state thereof, to secure partial, progress, advance, or other payments pursuant to any contract or statute, or any debt incurred by NuStar Logistics or any subsidiary for the purpose of financing all or any part of the purchase price of, or the cost of constructing, developing, repairing or improving, the property or assets subject to such lien;



•

any lien securing industrial development, pollution control or similar revenue bonds;



•

any lien securing debt of NuStar Logistics or any subsidiary, all or a portion of the net proceeds of which are used, substantially concurrent with the funding thereof (and for purposes of determining such "substantial concurrence," taking into consideration, among other things, required notices to be given to holders of outstanding senior debt securities under the senior indenture in connection with such refunding, refinancing or repurchase, and the required corresponding durations thereof), to refinance, refund or repurchase all outstanding senior debt securities under the senior indenture including the amount of all accrued interest thereon and reasonable fees and expenses and premium, if any, incurred by NuStar Logistics or any subsidiary in connection therewith;

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•

any lien in favor of any person to secure obligations under the provisions of any letters of credit, bank guarantees, bonds or surety obligations required or requested by any governmental authority in connection with any contract or statute; or



•

any lien upon or deposits of any assets to secure performance of bids, trade contracts, leases or statutory obligations.

        "Consolidated Net Tangible Assets" means, at any date of determination, the total amount of assets after deducting therefrom:

•

all current liabilities, excluding (A) any current liabilities that by their terms are extendable or renewable at the option of the obligor thereon to a time more than 12 months after the time as of which the amount thereof is being computed, and (B) current maturities of long-term debt, and



•

the value, net of any applicable amortization, of all goodwill, trade names, trademarks, patents, unamortized debt discount and expense and other like intangible assets,

all as set forth on the consolidated balance sheet of NuStar Energy for its most recently completed fiscal quarter, prepared in accordance with United States generally accepted accounting principles.

Restrictions on Sale-Leasebacks

        The NuStar Logistics senior indenture provides that NuStar Logistics will not, and will not permit any subsidiary to, engage in the sale or transfer by NuStar Logistics or any subsidiary of any property or assets to a person (other than NuStar Logistics or a subsidiary) and the taking back by NuStar Logistics or any subsidiary, as the case may be, of a lease of such property or assets (a "Sale-Leaseback Transaction"), unless:

(1)

the Sale-Leaseback Transaction occurs within one year from the date of completion of the acquisition of the property or assets subject thereto or the date of the completion of construction, development or substantial repair or improvement, or commencement of full operations on such property or assets, whichever is later;



(2)

the Sale-Leaseback Transaction involves a lease for a period, including renewals, of not more than three years;



(3)

NuStar Logistics or such subsidiary would be entitled to incur debt secured by a lien on the property or assets subject thereto in a principal amount equal to or exceeding the Attributable Indebtedness from such Sale-Leaseback Transaction without equally and ratably securing the senior debt securities issued under the senior indenture; or



(4)

NuStar Logistics or such subsidiary, within a one-year period after such Sale-Leaseback Transaction, applies or causes to be applied an amount not less than the Attributable Indebtedness from such Sale-Leaseback Transaction to (A) the prepayment, repayment, redemption, reduction or retirement of Pari Passu Debt of NuStar Logistics, or (B) the expenditure or expenditures for property or assets used or to be used in the ordinary course of business of NuStar Logistics or its subsidiaries.

        Notwithstanding the foregoing, NuStar Logistics may, and may permit any of its subsidiaries to, effect any Sale-Leaseback Transaction that is not excepted by clauses (1) through (4), inclusive, above; provided that the Attributable Indebtedness from the Sale-Leaseback Transaction, together with the aggregate principal amount of then outstanding debt other than the senior debt securities secured by liens upon any property or assets of NuStar Logistics or its subsidiaries not excepted by clauses (1) through (10), inclusive, of the second paragraph of the limitation on liens covenant described above, do not exceed 10% of the Consolidated Net Tangible Assets.

        "Attributable Indebtedness," when used with respect to any Sale-Leaseback Transaction, means, as at the time of determination, the present value, discounted at the rate set forth or implicit in the terms of the lease included in the transaction, of the total obligations of the lessee for rental payments, other than amounts required to be paid on account of property taxes, maintenance, repairs, insurance,

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assessments, utilities, operating and labor costs and other items that constitute payments for property rights, during the remaining term of the lease included in the Sale-Leaseback Transaction, including any period for which the lease has been extended. In the case of any lease that is terminable by the lessee upon the payment of a penalty or other termination payment, the amount shall be the lesser of the amount determined assuming termination upon the first date the lease may be terminated, in which case the amount shall also include the amount of the penalty or termination payment, but no rent shall be considered as required to be paid under the lease subsequent to the first date upon which it may be so terminated, or the amount determined assuming no termination.

        "Pari Passu Debt" means any debt of NuStar Logistics, whether outstanding on the date any senior debt securities are issued under the senior indenture or thereafter created, incurred or assumed, unless in the case of any particular debt, the instrument creating or evidencing the same or pursuant to which the same is outstanding expressly provides that such debt shall be subordinated in right of payment to the senior debt securities.

Provisions Only in the NuStar Logistics Subordinated Indenture

Subordinated Debt Securities Subordinated to Senior Debt

        The subordinated debt securities will rank junior in right of payment to all of the Senior Debt of NuStar Logistics and NPOP. "Senior Debt" is generally defined to include all notes or other evidences of indebtedness for money, including guarantees, borrowed by NuStar Logistics and NPOP, as applicable, that are not expressly subordinate or junior in right of payment to any other indebtedness of NuStar Logistics or NPOP.

Payment Blockages

        The subordinated indenture will provide that no payment of principal, interest and any premium on the subordinated debt securities may be made in the event that NuStar Logistics fails to pay when due any amounts on any Senior Debt and in other instances specified in the subordinated indenture.

No Limitation on Amount of Senior Debt

        The subordinated indenture will not limit the amount of Senior Debt that NuStar Logistics may incur.

Consolidation, Merger or Asset Sale

        Pursuant to each of the indentures, NuStar Logistics may not consolidate with or merge into any other entity or sell, lease or transfer its properties and assets as, or substantially as, an entirety to, any entity, unless:

•

(a) in the case of a merger, NuStar Logistics is the surviving entity, or (b) the entity formed by such consolidation or into which NuStar Logistics is merged or the entity which acquires by sale or transfer, or which leases, NuStar Logistics' properties and assets as, or substantially as, an entirety expressly assumes the due and punctual payment of the principal of and any premium and interest on all the debt securities under the applicable indenture and the performance or observance of every covenant of the applicable indenture on the part of NuStar Logistics to be performed or observed and shall have expressly provided for conversion rights in respect of any series of outstanding securities with conversion rights;



•

the surviving entity or successor entity is an entity organized and existing under the laws of the United States of America, any state thereof or the District of Columbia;



•

immediately after giving effect to such transaction, no default or event of default shall have occurred and be continuing under the applicable indenture; and



•

NuStar Logistics has delivered to the trustee under the applicable indenture an officers' certificate and an opinion of counsel regarding compliance with the terms of the applicable indenture.

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Modification of Indentures

        NuStar Logistics may modify or amend each indenture if the holders of a majority in principal amount of the outstanding debt securities of all series issued under the indenture affected by the modification or amendment consent to it. Without the consent of the holders of each outstanding debt security affected, however, generally no modification may:

•

change the stated maturity of the principal of or any installment of principal of or interest on any debt security;



•

reduce the principal amount of, the interest rate on or the premium payable upon redemption of any debt security;



•

change the redemption date for any debt security;



•

reduce the principal amount of an original issue discount debt security payable upon acceleration of maturity;



•

change the place of payment where any debt security or any premium or interest on any debt security is payable;



•

change the coin or currency in which any debt security or any premium or interest on any debt security is payable;



•

impair the right to institute suit for the enforcement of any payment on any debt security;



•

modify the provisions of the applicable indenture in a manner adversely affecting any right to convert or exchange any debt security into another security;



•

reduce the percentage in principal amount of outstanding debt securities of any series necessary to modify the applicable indenture, to waive compliance with certain provisions of the applicable indenture or to waive certain defaults and their consequences; or



•

modify any of the above provisions.

        NuStar Logistics may modify or amend each indenture without the consent of any holders of the debt securities in certain circumstances, including:

•

to provide for the assumption of obligations of NuStar Logistics under such indenture and the debt securities issued thereunder by a successor;



•

to provide for the assumption of NuStar Energy's guarantee under such indenture by a successor;



•

to add covenants and events of default or to surrender any rights NuStar Logistics has under such indenture;



•

to secure the senior debt securities as described above under "Provisions Only in the Senior Indenture—Limitations on Liens;"



•

to make any change that does not adversely affect any outstanding debt securities of a series in any material respect;



•

to supplement such indenture in order to establish a new series of debt securities under such indenture;



•

to provide for successor trustees;



•

to cure any ambiguity, omission, defect or inconsistency;



•

to provide for uncertificated securities in addition to certificated securities;



•

to supplement any provision of such indenture necessary to permit or facilitate the defeasance and discharge of any series of debt securities issued thereunder so long as that action does not adversely affect the interests of the holders of any outstanding debt securities issued thereunder;

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•

to comply with the rules or regulations of any securities exchange or automated quotation system on which any of the debt securities issued thereunder may be listed or traded; and



•

to qualify such indenture under the Trust Indenture Act.

        The holders of a majority in principal amount of the outstanding debt securities of any series issued under either of the indentures may waive past defaults, with respect to such series, under such indenture. The holders of a majority in principal amount of the outstanding debt securities of all affected series issued under either of the indentures (voting as one class) may waive compliance by NuStar Logistics with its covenants with respect to the debt securities of those series. Those holders may not, however, waive any default in any payment on any debt security of that series or compliance with a provision that cannot be modified or amended without the consent of each holder affected.

Events of Default and Remedies

        "Event of Default" when used in each indenture, means any of the following with respect to debt securities of any series:

•

failure to pay interest on any debt security of that series for 30 days;



•

failure to pay the principal of or any premium on any debt security of that series when due;



•

failure to perform any other covenant or warranty in such indenture (other than a term, covenant or warranty a default in whose performance or whose breach is elsewhere in this event of default section specifically dealt with or which has expressly been included in the applicable indenture solely for the benefit of a series of debt securities other than that series) that continues for 60 days after written notice is given to NuStar Logistics by the trustee or to NuStar Logistics and the trustee by the holders of at least 25% in principal amount of the outstanding debt securities of the series, specifying such default and requiring it to be remedied and stating that such notice is a "Notice of Default" under the applicable indenture;



•

failure to pay any indebtedness of NuStar Logistics for borrowed money in excess of $25 million, whether at final maturity (after the expiration of any applicable grace periods) or upon acceleration of the maturity thereof, if such indebtedness is not discharged, or such acceleration is not annulled, within 10 days after written notice is given to NuStar Logistics by the trustee or to NuStar Logistics and the trustee by the holders of at least 25% in principal amount of the outstanding debt securities of the series, specifying such default and requiring it to be remedied and stating that such notice is a "Notice of Default" under the applicable indenture;



•

certain events of bankruptcy, insolvency or reorganization of NuStar Logistics; or



•

any other Event of Default with respect to debt securities of that series included in such indenture or supplemental indenture.

        The subordination provisions of the subordinated indenture do not affect the obligation of NuStar Logistics, which is absolute and unconditional, to pay, when due, the principal of and any premium and interest on the subordinated debt securities. In addition, such subordination provisions do not prevent the occurrence of any default under the subordinated indenture.

        An Event of Default for a particular series of debt securities does not necessarily constitute an Event of Default for any other series of debt securities issued under either indenture. The trustee may withhold notice to the holders of debt securities of any default, except in the payment of principal or interest, if it considers such withholding of notice to be in the best interests of the holders.

        If an Event of Default for any series of debt securities occurs and continues, the trustee or the holders of at least 25% in aggregate principal amount of the debt securities of the series may declare the entire principal of (or, if any of the debt securities of that series are original issue discount debt securities, the portion of the principal specified in the terms of those securities), and accrued but

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unpaid interest, if any, on all the debt securities of that series to be due and payable immediately. If this happens, subject to certain conditions, the holders of a majority of the aggregate principal amount of the debt securities of that series can rescind the declaration. If an event of default relating to certain events of bankruptcy, insolvency or reorganization occurs, the entire principal of all the outstanding notes shall be due and payable immediately without further action or notice.

        Other than its duties in case of a default, a trustee is not obligated to exercise any of its rights or powers under either indenture at the request, order or direction of any holders, unless the holders offer the trustee reasonable indemnity. If they provide this reasonable indemnification, the holders of a majority in principal amount of any series of debt securities may, subject to certain limitations, direct the time, method and place of conducting any proceeding or any remedy available to the trustee, or exercising any power conferred upon the trustee, for any series of debt securities.

Registration of Debt Securities

        NuStar Logistics may issue debt securities of a series in registered, bearer, coupon or global form.

Minimum Denominations

        Unless the prospectus supplement for each issuance of debt securities states otherwise, the debt securities will be issued in registered form in amounts of $1,000 each or multiples of $1,000.

No Personal Liability of General Partner

        Unless otherwise stated in a prospectus supplement and supplemental indenture relating to a series of debt securities being offered, the general partner of NuStar Logistics and its directors, officers, employees and stockholders (in their capacity as such) will not have any liability for NuStar Logistics' obligations under the indentures or the debt securities. In addition, NuStar GP, LLC, the general partner of NuStar Energy's general partner, and the directors, officers, employees and members of NuStar GP, LLC will not have any liability for NuStar Energy's or NPOP's obligations as a guarantor under the indentures or the debt securities. Each holder of debt securities by accepting a debt security waives and releases all such liability. The waiver and release are part of the consideration for the issuance of the debt securities. This waiver may not be effective, however, to waive liabilities under the federal securities laws and it is the view of the SEC that such a waiver is against public policy.

Payment and Transfer

        Principal, interest and any premium on fully registered securities will be paid at designated places. Payment will be made by check mailed to the persons in whose names the debt securities are registered on days specified in the indentures or any prospectus supplement. Debt securities payments in other forms will be paid at a place designated by NuStar Logistics and specified in a prospectus supplement.

        Fully registered securities may be transferred or exchanged at the corporate trust office of the trustee or at any other office or agency maintained by NuStar Logistics for such purposes, without the payment of any service charge except for any tax or governmental charge.

Form, Exchange, Registration and Transfer

        Debt securities of any series will be exchangeable for other debt securities of the same series, the same total principal amount and the same terms but in different authorized denominations in accordance with the applicable indenture. Holders may present debt securities for registration of transfer at the office of the security registrar or any transfer agent NuStar Logistics designates. The security registrar or transfer agent will effect the transfer or exchange when it is satisfied with

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the documents of title and identity of the person making the request. NuStar Logistics will not charge a service charge for any registration of transfer or exchange of the debt securities. NuStar Logistics may, however, require the payment of any tax or other governmental charge payable for that registration.

        NuStar Logistics will appoint the trustee under each indenture as security registrar for the debt securities issued under that indenture. NuStar Logistics is required to maintain an office or agency for transfers and exchanges in each place of payment. NuStar Logistics may at any time designate additional transfer agents for any series of debt securities. In the case of any redemption in part, NuStar Logistics will not be required:

•

to issue, register the transfer of or exchange debt securities of a series either during a period beginning 15 business days prior to the selection of debt securities of that series for redemption and ending on the close of business on the day of mailing of the relevant notice of redemption; or



•

to register the transfer of or exchange any debt security, or portion of any debt security, called for redemption, except the unredeemed portion of any debt security NuStar Logistics is redeeming in part.

Discharging NuStar Logistics' Obligations

        NuStar Logistics may choose to either discharge its obligations on the debt securities of any series in a legal defeasance, or to release itself from its covenant restrictions on the debt securities of any series in a covenant defeasance. NuStar Logistics may do so at any time on the 91st day after it deposits with the applicable trustee sufficient cash or government securities to pay the principal, interest, any premium and any other sums due on the stated maturity date or a redemption date of the debt securities of the series. If NuStar Logistics chooses the legal defeasance option, the holders of the debt securities of the series will not be entitled to the benefits of the applicable indenture except for registration of transfer and exchange of debt securities, replacement of lost, stolen or mutilated debt securities, conversion or exchange of debt securities, sinking fund payments and receipt of principal and interest on the original stated due dates or specified redemption dates.

        NuStar Logistics may discharge its obligations under the indentures or release itself from covenant restrictions only if it meets certain requirements. Among other things, NuStar Logistics must deliver to the trustee an opinion of its legal counsel to the effect that holders of the series of debt securities will not recognize income, gain or loss for federal income tax purposes as a result of such defeasance and will be subject to federal income tax on the same amount and in the same manner and at the same times as would have been the case if such deposit and defeasance had not occurred. In the case of legal defeasance only, this opinion must be based on either a ruling received from or published by the IRS or change in federal income tax law. NuStar Logistics may not have a default on the debt securities discharged on the date of deposit. The discharge may not violate any of its agreements. The discharge may not result in NuStar Logistics becoming an investment company in violation of the Investment Company Act of 1940.

The Trustee

Resignation or Removal of Trustee

        Under provisions of the indentures and the Trust Indenture Act of 1939, as amended, governing trustee conflicts of interest, any uncured Event of Default with respect to any series of senior debt securities will force the trustee to resign as trustee under either the subordinated indenture or the senior indenture. Also, any uncured Event of Default with respect to any series of subordinated debt securities will force the trustee to resign as trustee under either the senior indenture or the subordinated indenture. Any resignation will require the appointment of a successor trustee under the applicable indenture in accordance with the terms and conditions of such indenture. NuStar Logistics may appoint a separate trustee for any series of debt securities. The term "trustee" refers to the trustee appointed with respect to any such series of debt securities. The holders of a majority in aggregate principal amount of the debt securities of any series may remove the trustee with respect to the debt securities of such series.

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Limitations on Trustee if it is a Creditor of NuStar Logistics

        There are limitations on the right of the trustee, in the event that it becomes a creditor of NuStar Logistics, to obtain payment of claims in certain cases, or to realize on certain property received in respect of any such claim as security or otherwise.

Annual Trustee Report to Holders of Debt Securities

        The trustee is required to submit an annual report to the holders of the debt securities regarding, among other things, the trustee's eligibility to serve as such, the priority of the trustee's claims regarding certain advances made by it, and any action taken by the trustee materially affecting the debt securities.

Certificates and Opinions to be Furnished to Trustee

        Every application by NuStar Logistics for action by the trustee shall be accompanied by a certificate of certain of NuStar Logistics' officers and an opinion of counsel (who may be NuStar Logistics' counsel) stating that, in the opinion of the signers, all conditions precedent to such action have been complied with by NuStar Logistics.

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DESCRIPTION OF NPOP DEBT SECURITIES

        The following description sets forth the general terms and provisions that apply to the debt securities that may be offered by NPOP. Each prospectus supplement will state the particular terms that will apply to the debt securities included in the supplement.

        The senior debt securities that may be offered by NPOP will be issued under an indenture, dated February 21, 2001, between NPOP and Wells Fargo Bank, National Association (as successor-in-interest to JPMorgan Chase Bank, N.A.), as trustee, as supplemented by the supplemental indentures thereto (the "Senior Indenture"). If NPOP issues one or more series of senior debt securities, the terms of the senior debt securities will include those expressly set forth in the Senior Indenture and those made part of the Senior Indenture by reference to the Trust Indenture Act of 1939, as amended. If NPOP issues one or more series of subordinated debt securities, it will issue them under a separate indenture containing subordination provisions (the "Subordinated Indenture"). The Senior Indenture and the form of the Subordinated Indenture have been filed as exhibits to the registration statement of which this prospectus is a part.

        You should read the indentures for provisions that may be important to you because the indentures, and not this description, govern your rights as a holder of debt securities. References in this prospectus to an "Indenture" refer to the particular Indenture under which a series of debt securities is issued.

General

        Neither indenture limits the amount of debt securities that may be issued thereunder. Debt securities may be issued under the indentures from time to time in separate series, each up to the aggregate amount authorized for such series.

Guarantees

        NPOP's payment obligations under any series of debt securities will be fully and unconditionally guaranteed by NuStar Energy and NuStar Logistics, jointly and severally. Each of NuStar Energy and NuStar Logistics will execute a notation of guarantee as further evidence of its guarantee. The applicable prospectus supplement will describe the terms of any guarantees by NuStar Energy and NuStar Logistics.

        Pursuant to the guarantees, each of NuStar Energy and NuStar Logistics will guarantee the due and punctual payment of the principal of, and interest and premium, if any, on, the debt securities of a particular series, when the same shall become due, whether by acceleration or otherwise. The guarantees will be enforceable against NuStar Energy and NuStar Logistics without any need to first enforce any debt securities against NPOP.

        The guarantees of the senior debt securities:

•

will be the unsecured and unsubordinated general obligations of NuStar Energy and NuStar Logistics; and



•

will rank on a parity with all of the other unsecured and unsubordinated indebtedness of NuStar Energy and NuStar Logistics.

        If a series of NPOP subordinated debt securities is guaranteed by NuStar Energy and NuStar Logistics, then the guarantees will be subordinated to the senior debt of NuStar Energy and NuStar Logistics, respectively, to substantially the same extent as the series of subordinated debt securities is subordinated to the senior debt of NPOP.

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Specific Terms of Each Series of NPOP Debt Securities in the Prospectus Supplement

        A prospectus supplement and a supplemental indenture (or a resolution of the Board of Directors of NuStar GP, LLC and accompanying officers' certificate) relating to any series of debt securities being offered will include specific terms relating to the offering. These terms will include some or all of the following:

•

the form and title of the debt securities;



•

the total principal amount of the debt securities;



•

the date or dates on which the debt securities may be issued;



•

the dates on which the principal and premium, if any, of the debt securities will be payable;



•

the interest rate which the debt securities will bear and the interest payment dates for the debt securities;



•

any optional redemption provisions;



•

any sinking fund or other provisions that would obligate NPOP to repurchase or otherwise redeem the debt securities;



•

whether the debt securities may be issued in amounts other than $1,000 each or multiples thereof;



•

the portion of the principal amount which will be payable if the maturity of the debt securities is accelerated;



•

any changes to or additional Events of Default or covenants;



•

the subordination, if any, of the debt securities and any changes to the subordination provisions of the Indenture; and



•

any other terms of the debt securities.

        The prospectus supplement will also describe any material United States federal income tax consequences or other special considerations regarding the applicable series of debt securities, including those relating to:

•

debt securities with respect to which payments of principal, premium or interest are determined with reference to an index or formula, including changes in prices of particular securities, currencies or commodities;



•

debt securities with respect to which principal, premium or interest is payable in a foreign or composite currency;



•

debt securities that are issued at a discount below their stated principal amount, bearing no interest or interest at a rate that at the time of issuance is below market rates; and



•

variable rate debt securities that are exchangeable for fixed rate debt securities.

        At the option of NPOP, we may make interest payments, by check mailed to the registered holders of debt securities or, if so stated in the applicable prospectus supplement, at the option of a holder by wire transfer to an account designated by the holder.

        Unless otherwise provided in the applicable prospectus supplement, fully registered securities may be transferred or exchanged at the corporate trust office of the Trustee or at any other office or agency maintained by NPOP for such purposes, subject to the limitations provided in the Indenture, without the payment of any service charge, other than any applicable tax or governmental charge.

        Any funds we pay to a paying agent for the payment of amounts due on any debt securities that remain unclaimed for two years will be returned to NPOP, and the holders of the debt securities must thereafter look only to NPOP for payment thereof.

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Covenants

        A series of NPOP debt securities may contain certain financial and other covenants applicable to NPOP and the subsidiaries of NPOP. A description of any such affirmative and negative covenants will be contained in the prospectus supplement applicable to such series.

The Trustee

        We may appoint a separate Trustee for any series of debt securities. As used herein in the description of a series of debt securities, the term "Trustee" refers to the Trustee appointed with respect to any such series of debt securities.

        We may maintain banking and other commercial relationships with the Trustee and its affiliates in the ordinary course of business, and the Trustee may own debt securities.

Events of Default

        Each of the following will be an "Event of Default" under the indentures with respect to a series of debt securities:

•

default in any payment of interest on any debt securities of that series when due, continued for 60 days;



•

default in the payment of principal of or premium, if any, on any debt securities of that series when due at its stated maturity, upon redemption or otherwise;



•

default in the payment of any sinking fund payment on any debt securities of that series when due;



•

failure by NPOP for 60 days after NPOP's receipt of notice from the Trustee or the holders of at least 25% in principal amount of the outstanding debt securities of that series to comply with the other agreements contained in the Indenture, any supplement to the indentures or any board resolution authorizing the issuance of that series; or



•

certain events of bankruptcy, insolvency or reorganization of NPOP.

        If an Event of Default occurs and is continuing, the Trustee by notice to NPOP, or the holders of at least 25% in principal amount of the outstanding debt securities of that series by notice to NPOP and the Trustee, may, and the Trustee at the request of such holders shall, declare the principal of, premium, if any, and accrued and unpaid interest, if any, on all the debt securities of that series to be due and payable. Upon such a declaration, the principal, premium and accrued and unpaid interest will be due and payable immediately. The holders of a majority in principal amount of the outstanding debt securities of a series may waive all past defaults (except with respect to nonpayment of principal, premium, if any, or interest) and rescind any such acceleration with respect to the debt securities of that series and its consequences if rescission would not conflict with any judgment or decree of a court of competent jurisdiction and all existing Events of Default, other than the nonpayment of the principal of, premium, if any, and interest on the debt securities of that series that have become due solely by such declaration of acceleration, have been cured or waived.

        Subject to the provisions of the indentures relating to the duties of the Trustee, if an Event of Default occurs and is continuing, the Trustee will be under no obligation to exercise any of the rights or powers under the indentures at the request or direction of any of the holders unless such holders have offered to the Trustee reasonable indemnity or security against any loss, liability or expense. Except to enforce the right to receive payment of principal, premium, if any, or interest when due, no holder may pursue any remedy with respect to the indentures or any series of the debt securities unless:

•

such holder has previously given the Trustee notice that an Event of Default with respect to that series of debt securities is continuing;

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•

holders of at least 25% in principal amount of the outstanding debt securities of that series have requested the Trustee to pursue the remedy;



•

such holders have offered the Trustee reasonable indemnity against any loss, liability or expense;



•

the Trustee has not complied with such request within 60 days after the receipt of the request and the offer of indemnity; and



•

the holders of a majority in principal amount of the outstanding debt securities of that series have not given the Trustee a direction that, in the opinion of the Trustee, is inconsistent with such request within such 60-day period.

        Subject to certain restrictions, the holders of a majority in principal amount of the outstanding debt securities of a series are given the right to direct the time, method and place of conducting any proceeding for any remedy available to the Trustee or of exercising any trust or power conferred on the Trustee with respect to that series of debt securities. The Trustee, however, may refuse to follow any direction that conflicts with law or the indentures or that the Trustee determines is unduly prejudicial to the rights of any other holder or that would involve the Trustee in personal liability. Prior to taking any action under the indentures, the Trustee will be entitled to indemnification satisfactory to it in its sole discretion against all losses and expenses caused by taking or not taking such action.

        The indentures provide that if an Event of Default occurs and is continuing and is known to the Trustee, the Trustee must mail to each holder notice of the Event of Default within 90 days after it occurs. Except in the case of a default in the payment of principal of, premium, if any, or interest on any debt securities, the Trustee may withhold notice if and so long as the committee of responsible officers of the Trustee in good faith determines that withholding notice is in the interests of the holders. In addition, we are required to deliver to the Trustee, within 4 months after the end of each fiscal year, a compliance certificate indicating we have complied with all covenants contained in the indentures or whether any default or Event of Default has occurred during the previous year. We are also required to deliver to the Trustee, within 30 days after the occurrence thereof, written notice of any Event of Default, its status and what action we are taking or propose to take with respect to the default.

Amendments and Waivers

        Modifications and amendments to the indentures may be made by NPOP and the Trustee with the consent of the holders of a majority in principal amount of all debt securities then outstanding under the indentures (including consents obtained in connection with a tender offer or exchange offer for the debt securities). However, without the consent of each holder of outstanding debt securities of each series affected thereby, no amendment may, among other things:

•

reduce the percentage in principal amount of debt securities whose holders must consent to an amendment;



•

reduce the rate of or extend the time for payment of interest on any debt securities;



•

reduce the principal of or extend the stated maturity of any debt securities;



•

reduce the premium payable upon the redemption of any debt securities or change the time at which any debt securities may be redeemed under an optional redemption or any similar provision;



•

make any debt securities payable in other than U.S. dollars;



•

impair the right of any holder to receive payment of, premium, if any, principal of and interest on such holder's debt securities on or after the due dates therefor or to institute suit for the enforcement of any payment on or with respect to such holder's debt securities;



•

release any security that has been granted in respect of the debt securities;

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•

waive a redemption payment with respect to a debt security other than as required by a covenant in the applicable supplemental indenture;



•

except as permitted under the indentures or any supplemental indenture, with respect to debt securities that are guaranteed, release any guarantor from its obligations under the indentures or supplemental indenture or under its guarantee or change any guarantee in any manner that would adversely affect the rights of holders of those debt securities; or



•

make any change in the amendment provisions which require each holder's consent or in the waiver provisions.

        The holders of a majority in aggregate principal amount of the outstanding debt securities of each series affected thereby, on behalf of all such holders, may waive compliance by NPOP with certain restrictive provisions of the indentures. Subject to certain rights of the Trustee as provided in the indentures, the holders of a majority in aggregate principal amount of debt securities of each series affected thereby, on behalf of all such holders, may waive any past default under the indentures (including any such waiver obtained in connection with a tender offer or exchange offer for the debt securities), except a default in the payment of principal, premium or interest or a default in respect of a provision that under the indentures cannot be modified or amended without the consent of all holders of the series of debt securities that is affected.

        Without the consent of any holder, we and the Trustee may, among other things, amend the indentures to:

•

cure any ambiguity, defect, omission, error or inconsistency;



•

convey, transfer, assign, mortgage or pledge any property to or with the Trustee;



•

provide for the assumption by a successor corporation, partnership, trust or limited liability company of the obligations of NPOP under the indentures;



•

make any change that would provide any additional rights or benefits to the holders of debt securities or that does not adversely affect the rights of any holder;



•

add or appoint a successor or separate Trustee;



•

comply with any requirement of the Securities and Exchange Commission in connection with the qualification of the indentures under the Trust Indenture Act; or



•

add any additional Events of Default.

        The consent of the holders is not necessary under the indentures to approve the particular form of any proposed amendment. It is sufficient if such consent approves the substance of the proposed amendment. After an amendment under the indentures becomes effective, we are required to mail to the holders a notice briefly describing such amendment. However, the failure to give such notice to all the holders, or any defect therein, will not impair or affect the validity of the amendment.

Defeasance

        At any time we may terminate the obligations of NPOP under a series of debt securities and the indentures in a "legal defeasance." If we choose to terminate the obligations of NPOP in a legal defeasance, the holders of the debt securities of the series will not be entitled to the benefits of the related indenture, except for certain obligations, including those respecting the defeasance trust and obligations to register the transfer or exchange of the debt securities, to replace mutilated, destroyed, lost or stolen debt securities and to maintain a registrar and paying agent in respect of the debt securities. At any time we may terminate the obligations of NPOP under covenants applicable to a series of debt securities and described in the prospectus supplement applicable to such series (other than as described in such prospectus supplement) in a "covenant defeasance."

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        We may exercise NPOP's legal defeasance option notwithstanding NPOP's prior exercise of NPOP's covenant defeasance option. If we exercise NPOP's legal defeasance option, payment of the affected series of debt securities may not be accelerated because of an Event of Default with respect thereto. If we exercise NPOP's covenant defeasance option, payment of the affected series of debt securities may not be accelerated because of an Event of Default specified in the fourth bullet point under "Events of Default" above.

        In order to exercise either defeasance option, we must irrevocably deposit in trust with the Trustee money or certain U.S. government obligations for the payment of principal, premium, if any, and interest on the series of debt securities to redemption or maturity, as the case may be (a "defeasance trust") and must comply with certain other conditions, including that no default has occurred and is continuing after the deposit in trust and the delivery to the Trustee of an opinion of counsel to the effect that holders of the series of debt securities will not recognize income, gain or loss for federal income tax purposes as a result of such defeasance and will be subject to federal income tax on the same amount and in the same manner and at the same times as would have been the case if such deposit and defeasance had not occurred. In the case of legal defeasance only, such opinion of counsel must be based on a ruling of the Internal Revenue Service or other change in applicable federal income tax law.

Subordination

        Debt securities of a series may be subordinated to Senior Indebtedness (as defined below) to the extent set forth in the prospectus supplement relating to such series. Subordinated debt securities will be subordinate in right of payment, to the extent and in the manner set forth in the Indenture and the prospectus supplement relating to such series, to the prior payment of all of the indebtedness of NPOP that is designated as "Senior Indebtedness" with respect to the series. "Senior Indebtedness" is defined generally to include all notes or other evidences of indebtedness for money borrowed by NPOP including any guarantee of a NPOP debt security by NuStar Energy or NuStar Logistics, provided that these obligations are not expressed to be subordinate or junior in right of payment to any of the other indebtedness of NPOP.

        Upon any payment or distribution of NPOP's assets or upon a total or partial liquidation or dissolution of NPOP, or in a bankruptcy, receivership or similar proceeding relating to NPOP, the holders of Senior Indebtedness of NPOP shall be entitled to receive payment in full in cash of the Senior Indebtedness before the holders of subordinated debt securities shall be entitled to receive any payment of principal, premium or interest with respect to the subordinated debt securities, and until the Senior Indebtedness is paid in full, any distribution to which holders of subordinated debt securities would otherwise be entitled shall be made to the holders of Senior Indebtedness.

        We may not make any payments of principal, premium, if any, or interest with respect to subordinated debt securities, make any deposit for the purpose of defeasance of the subordinated debt securities, or repurchase, redeem or otherwise retire (except, in the case of subordinated debt securities that provide for a mandatory sinking fund, by NPOP's delivery of subordinated debt securities to the Trustee in satisfaction of NPOP's sinking fund obligation) any subordinated debt securities if (a) any principal, premium or interest with respect to Senior Indebtedness is not paid within any applicable grace period (including at maturity), or (b) any other default on Senior Indebtedness occurs and the maturity of the Senior Indebtedness is accelerated in accordance with its terms, unless, in either case, the default has been cured or waived and the acceleration has been rescinded, the Senior Indebtedness has been paid in full in cash, or we and the Trustee receive written notice approving the payment from the representatives of each issue of "Designated Senior Indebtedness" (which, unless otherwise provided in the prospectus supplement relating to the series of subordinated debt securities, will include indebtedness for borrowed money under a bank credit agreement ("Bank Indebtedness") and any other specified issue of Senior Indebtedness of at least $100 million or other indebtedness of borrowed money that we may designate). During the continuance of any default (other than a default described in clause (a) or (b) above), with respect to any Senior Indebtedness pursuant to which the maturity thereof may be accelerated immediately without further notice (except such notice as may be

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required to effect the acceleration) or the expiration of any applicable grace periods, we may not pay the subordinated debt securities for a period, the "Payment Blockage Period," commencing on the receipt by NPOP and the Trustee of written notice of the default from the representative of any Designated Senior Indebtedness specifying an election to effect a Payment Blockage Period, a "Blockage Notice." The Payment Blockage Period may be terminated before its expiration by written notice to the Trustee and to NPOP from the person or persons who gave the Blockage Notice, by repayment in full in cash of the Senior Indebtedness with respect to which the Blockage Notice was given, or because the default giving rise to the Payment Blockage Period is no longer continuing. Unless the holders of Senior Indebtedness shall have accelerated the maturity thereof, we may resume payments on the subordinated debt securities after the expiration of the Payment Blockage Period. Unless otherwise provided in the prospectus supplement relating to the series of subordinated debt securities, not more than one Blockage Notice may be given in any period of 360 consecutive days unless the first Blockage Notice within the 360-day period is given by or on behalf of holders of Designated Senior Indebtedness other than the Bank Indebtedness, in which case, the representative of the Bank Indebtedness may give another Blockage Notice within the period. In no event, however, may the total number of days during which any Payment Blockage Period or Periods is in effect exceed 179 days in the aggregate during any period of 360 consecutive days. After all Senior Indebtedness is paid in full and until the subordinated debt securities are paid in full, holders of the subordinated debt securities shall be subrogated to the rights of holders of Senior Indebtedness to receive distributions applicable to Senior Indebtedness.

        By reason of the subordination, in the event of insolvency, the creditors of NPOP who are holders of Senior Indebtedness, as well as certain of the general creditors of NPOP, may recover more, ratably, than the holders of the subordinated debt securities.

Governing Law

        The indentures provide that they and the debt securities will be governed by, and construed in accordance with, the laws of the State of New York.

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BOOK-ENTRY SECURITIES

        Unless otherwise specified in the applicable prospectus supplement, NuStar Energy, NuStar Logistics or NPOP, as the case may be, will issue to investors securities, other than NuStar Energy common units, in the form of one or more book-entry certificates registered in the name of a depository or a nominee of a depository. Unless otherwise specified in the applicable prospectus supplement, the depository will be The Depository Trust Company, also referred to as DTC. We have been informed by DTC that its nominee will be Cede & Co. Accordingly, Cede is expected to be the initial registered holder of all securities that are issued in book-entry form.

        No person that acquires a beneficial interest in securities issued in book-entry form will be entitled to receive a certificate representing those securities, except as set forth in this prospectus or in the applicable prospectus supplement. Unless and until definitive securities are issued under the limited circumstances described below, all references to actions by holders or beneficial owners of securities issued in book-entry form will refer to actions taken by DTC upon instructions from its participants, and all references to payments and notices to holders or beneficial owners will refer to payments and notices to DTC or Cede, as the registered holder of such securities.

        DTC has informed us that it is:

•

a limited-purpose trust company organized under New York banking laws;



•

a "banking organization" within the meaning of the New York banking laws;



•

a member of the Federal Reserve System;



•

a "clearing corporation" within the meaning of the New York Uniform Commercial Code; and



•

a "clearing agency" registered under the Securities Exchange Act of 1934.

        DTC has also informed us that it was created to:

•

hold securities for "participants"; and



•

facilitate the computerized settlement of securities transactions among participants through computerized electronic book-entry changes in participants' accounts, thereby eliminating the need for the physical movement of securities certificates.

        Participants have accounts with DTC and include securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations. Indirect access to the DTC system also is available to indirect participants such as banks, brokers, dealers and trust companies that clear through or maintain a custodial relationship with a participant, either directly or indirectly.

        Persons that are not participants or indirect participants but desire to buy, sell or otherwise transfer ownership of or interests in securities may do so only through participants and indirect participants. Under the book-entry system, beneficial owners may experience some delay in receiving payments, as payments will be forwarded by our agent to Cede, as nominee for DTC. DTC will forward these payments to its participants, which thereafter will forward them to indirect participants or beneficial owners. Beneficial owners will not be recognized by the applicable registrar, transfer agent, trustee or depositary as registered holders of the securities entitled to the benefits of the certificate, the indenture or any deposit agreement. Beneficial owners that are not participants will be permitted to exercise their rights as an owner only indirectly through participants and, if applicable, indirect participants.

        Under the current rules and regulations affecting DTC, DTC will be required to make book-entry transfers of securities among participants and to receive and transmit payments to participants. Participants and indirect participants with which beneficial owners of securities have accounts are also required by these rules to make book-entry transfers and receive and transmit such payments on behalf of their respective account holders.

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        Because DTC can act only on behalf of participants, who in turn act only on behalf of other participants or indirect participants, and on behalf of banks, trust companies and other persons approved by it, the ability of a beneficial owner of securities issued in book-entry form to pledge those securities to persons or entities that do not participate in the DTC system may be limited due to the unavailability of physical certificates for the securities.

        DTC has advised us that it will take any action permitted to be taken by a registered holder of any securities under the certificate, the indenture or any deposit agreement only at the direction of one or more participants to whose accounts with DTC the securities are credited.

        According to DTC, the information with respect to DTC has been provided to its participants and other members of the financial community for informational purposes only and is not intended to serve as a representation, warranty, or contract modification of any kind.

        Unless otherwise specified in the applicable prospectus supplement, a book-entry security will be exchangeable for definitive securities registered in the names of persons other than DTC or its nominee only if:

•

DTC notifies us that it is unwilling or unable to continue as depositary for the book-entry security or DTC ceases to be a clearing agency registered under the Securities Exchange Act of 1934 at a time when DTC is required to be so registered;



•

we execute and deliver to the applicable registrar, transfer agent, trustee and/or depositary an order complying with the requirements of the certificate, the indenture or any deposit agreement that the book-entry security will be so exchangeable; or



•

in the case of debt securities, an event of default with respect to the applicable series of debt securities has occurred and is continuing.

        Any book-entry security that is exchangeable in accordance with the preceding sentence will be exchangeable for securities registered in such names as DTC directs.

        If one of the events described in the immediately preceding paragraph occurs, DTC is generally required to notify all participants of the availability through DTC of definitive securities. Upon surrender by DTC of the book-entry security representing the securities and delivery of instructions for re-registration, the registrar, transfer agent, trustee or depositary, as the case may be, will reissue the securities as definitive securities. After reissuance of the securities, such persons will recognize the beneficial owners of such definitive securities as registered holders of securities.

        Except as described above:

•

a book-entry security may not be transferred except as a whole book-entry security by or among DTC, a nominee of DTC and/or a successor depository appointed by us; and



•

DTC may not sell, assign or otherwise transfer any beneficial interest in a book-entry security unless the beneficial interest is in an amount equal to an authorized denomination for the securities evidenced by the book-entry security.

        None of us, the trustee, any registrar and transfer agent or any depositary, or any agent of any of them, will have any responsibility or liability for any aspect of DTC's or any participant's records relating to, or for payments made on account of, beneficial interests in a book-entry security.

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MATERIAL TAX CONSEQUENCES

        This section is a discussion of the material tax considerations that may be relevant to prospective unitholders who are individual citizens or residents of the U.S. and, unless otherwise noted in the following discussion, is the opinion of Andrews Kurth LLP, counsel to our general partner and us, insofar as it relates to matters of U.S. federal income tax law and legal conclusions with respect to those matters. This section is based upon current provisions of the Internal Revenue Code of 1986, as amended, or the Internal Revenue Code, existing and proposed regulations and current administrative rulings and court decisions, all of which are subject to change. Later changes in these authorities may cause the tax consequences to vary substantially from the consequences described below. Unless the context otherwise requires, references in this section to "us," "we" or "NuStar Energy" are references to NuStar Energy L.P.

        The following discussion does not address all federal income tax matters affecting us or the unitholders. Moreover, the discussion focuses on unitholders who are individual citizens or residents of the U.S. and has only limited application to corporations, estates, trusts, nonresident aliens or other unitholders subject to specialized tax treatment, such as tax-exempt institutions, foreign persons, individual retirement accounts (IRAs), real estate investment trusts (REITs), employee benefit plans or mutual funds. Accordingly, we urge each prospective unitholder to consult, and depend on, his own tax advisor in analyzing the federal, state, local and foreign tax consequences particular to him of the ownership or disposition of the common units.

        All statements as to matters of law and legal conclusions, but not as to factual matters, contained in this section, unless otherwise noted, are the opinion of Andrews Kurth LLP and are based on the accuracy of the representations made by us and our general partner.

        No ruling has been or will be requested from the IRS regarding our status as a partnership for federal income tax purposes or any matter affecting prospective unitholders. Instead, we will rely on opinions and advice of Andrews Kurth LLP. Unlike a ruling, an opinion of counsel represents only that counsel's best legal judgment and does not bind the IRS or the courts. Accordingly, the opinions and statements made in this discussion may not be sustained by a court if contested by the IRS. Any contest of this sort with the IRS may materially and adversely impact the market for the common units and the prices at which the common units trade. In addition, the costs of any contest with the IRS, principally legal, accounting and related fees, will result in a reduction in cash available to pay distributions to our unitholders and our general partner and thus will be borne indirectly by our unitholders and our general partner. Furthermore, the tax treatment of us, or of an investment in us, may be significantly modified by future legislative or administrative changes or court decisions. Any modifications may or may not be retroactively applied.

        For the reasons described below, Andrews Kurth LLP has not rendered an opinion with respect to the following specific federal income tax issues:

•

the treatment of a unitholder whose common units are loaned to a short seller to cover a short sale of common units (please read "—Tax Consequences of Unit Ownership—Treatment of Short Sales");



•

whether our monthly convention for allocating taxable income and losses is permitted by existing Treasury Regulations (please read "—Disposition of Common Units—Allocations Between Transferors and Transferees"); and



•

whether our method for depreciating Section 743 adjustments is sustainable in certain cases (please read "—Tax Consequences of Unit Ownership—Section 754 Election" and "—Uniformity of Units").

Partnership Status

        A partnership is not a taxable entity and incurs no federal income tax liability. Instead, each partner of a partnership is required to take into account his share of items of income, gain, loss and deduction of the partnership in computing his federal income tax liability, regardless of whether cash

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distributions are made to him by the partnership. Distributions by a partnership to a partner are generally not taxable to the partner unless the amount of cash distributed is in excess of the partner's adjusted basis in his partnership interest.

        Section 7704 of the Internal Revenue Code provides that publicly traded partnerships will, as a general rule, be taxed as corporations. However, an exception, referred to as the "Qualifying Income Exception," exists with respect to publicly traded partnerships of which 90% or more of the gross income for every taxable year consists of "qualifying income." Qualifying income includes income and gains derived from the refining, processing, transportation, storage and marketing of crude oil, natural gas and products thereof. Other types of qualifying income include interest (other than from a financial business), dividends, gains from the sale of real property and gains from the sale or other disposition of capital assets held for the production of income that otherwise constitutes qualifying income. We estimate that less than 3% of our current gross income is not qualifying income; however, this estimate could change from time to time. Based on and subject to this estimate, the factual representations made by us and our general partner and a review of the applicable legal authorities, Andrews Kurth LLP is of the opinion that at least 90% of our current gross income constitutes qualifying income. The portion of our income that is qualifying income can change from time to time.

        No ruling has been or will be sought from the IRS and the IRS has made no determination as to our status as a partnership for federal income tax purposes. Instead, we will rely on the opinion of Andrews Kurth LLP on such matters. It is the opinion of Andrews Kurth LLP that, based upon the Internal Revenue Code, its regulations, published revenue rulings and court decisions and the representations described below, we will be classified as a partnership and our operating partnerships will be disregarded as entities separate from us or classified as partnerships for federal income tax purposes.

        In rendering its opinion, Andrews Kurth LLP has relied on factual representations made by us and our general partner. The representations made by us and our general partner upon which Andrews Kurth LLP has relied include:

(a)

Neither we nor our operating partnerships have elected nor will elect to be treated as a corporation; and



(b)

For each taxable year, more than 90% of our gross income has been and will be income that Andrews Kurth LLP has opined or will opine is "qualifying income" within the meaning of Section 7704(d) of the Internal Revenue Code.

        If we fail to meet the Qualifying Income Exception, other than a failure that is determined by the IRS to be inadvertent and that is cured within a reasonable time after discovery (in which case the IRS may also require us to make adjustments with respect to our unitholders or pay other amounts), we will be treated as if we had transferred all of our assets, subject to liabilities, to a newly formed corporation, on the first day of the year in which we fail to meet the Qualifying Income Exception, in return for stock in that corporation, and then distributed that stock to the unitholders in liquidation of their interests in us. This deemed contribution and liquidation should be tax-free to unitholders and us except to the extent that our liabilities exceed the tax bases of our assets at that time. Thereafter, we would be treated as a corporation for federal income tax purposes.

        If we were taxable as a corporation in any taxable year, either as a result of a failure to meet the Qualifying Income Exception or otherwise, our items of income, gain, loss and deduction would be reflected only on our tax return rather than being passed through to the unitholders, and our net income would be taxed to us at corporate rates. In addition, any distribution made to a unitholder would be treated as either taxable dividend income, to the extent of our current or accumulated earnings and profits, or, in the absence of earnings and profits, a nontaxable return of capital, to the extent of the unitholder's tax basis in his common units, or taxable capital gain, after the unitholder's tax basis in his common units is reduced to zero. Accordingly, taxation as a corporation would result in a material reduction in a unitholder's cash flow and after-tax return and thus would likely result in a substantial reduction of the value of the units.

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        The discussion below is based on Andrews Kurth LLP's opinion that we will be classified as a partnership for federal income tax purposes.

Limited Partner Status

        Unitholders who have become limited partners of NuStar Energy will be treated as partners of NuStar Energy for federal income tax purposes. Also, unitholders whose common units are held in street name or by a nominee and who have the right to direct the nominee in the exercise of all substantive rights attendant to the ownership of their common units will be treated as partners of NuStar Energy for federal income tax purposes.

        A beneficial owner of common units whose units have been transferred to a short seller to complete a short sale would appear to lose his status as a partner with respect to those units for federal income tax purposes. Please read "—Tax Consequences of Unit Ownership—Treatment of Short Sales."

        Items of our income, gain, loss or deduction are not reportable by a unitholder who is not a partner for federal income tax purposes, and any cash distributions received by a unitholder who is not a partner for federal income tax purposes would therefore be fully taxable as ordinary income. These holders are urged to consult their own tax advisors with respect to their status as partners in NuStar Energy for federal income tax purposes. The references to "unitholders" in the discussion that follows are to persons who are treated as partners in NuStar Energy for federal income tax purposes.

Tax Consequences of Unit Ownership

        Flow-Through of Taxable Income.    We do not pay any federal income tax. Instead, each unitholder is required to report on his income tax return his share of our income, gains, losses and deductions without regard to whether corresponding cash distributions are received by him. Consequently, we may allocate income to a unitholder even if he has not received a cash distribution. Each unitholder will be required to include in income his allocable share of our income, gains, losses and deductions for our taxable year or years ending with or within his taxable year. Our taxable year ends on December 31.

        Treatment of Distributions.    Distributions by us to a unitholder generally will not be taxable to the unitholder for federal income tax purposes, except to the extent the amount of any such cash distribution exceeds his tax basis in his common units immediately before the distribution. Our cash distributions in excess of a unitholder's tax basis in his common units generally will be considered to be gain from the sale or exchange of the common units, taxable in accordance with the rules described under "—Disposition of Common Units" below. Any reduction in a unitholder's share of our liabilities for which no partner, including our general partner, bears the economic risk of loss, known as "non-recourse liabilities," will be treated as a distribution of cash to that unitholder. To the extent our distributions cause a unitholder's "at risk" amount to be less than zero at the end of any taxable year, the unitholder must recapture any losses deducted in previous years. Please read "—Limitations on Deductibility of Losses."

        A decrease in a unitholder's percentage interest in us because of our issuance of additional common units will decrease his share of our non-recourse liabilities, and thus will result in a corresponding deemed distribution of cash, which may constitute a non-pro rata distribution. A non-pro rata distribution of money or property may result in ordinary income to a unitholder, regardless of his tax basis in his common units, if the distribution reduces the unitholder's share of our "unrealized receivables," including depreciation recapture, and/or substantially appreciated "inventory items," both as defined in Section 751 of the Internal Revenue Code, and collectively, "Section 751 Assets." To that extent, he will be treated as having been distributed his proportionate share of the Section 751 Assets and having then exchanged those assets with us in return for the non-pro rata portion of the actual distribution made to him. This latter deemed exchange will generally result in the unitholder's realization of ordinary income, which will equal the excess of the non-pro rata portion of that distribution over the unitholder's tax basis for the share of Section 751 Assets deemed relinquished in the exchange.

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        Basis of Common Units.    A unitholder's initial tax basis for his common units will be the amount he paid for the common units plus his share of our non-recourse liabilities. That basis will be increased by his share of our income and by any increases in his share of our non-recourse liabilities. That basis generally will be decreased, but not below zero, by distributions from us, by the unitholder's share of our losses, by any decreases in his share of our non-recourse liabilities and by his share of our expenditures that are not deductible in computing taxable income and are not required to be capitalized. A unitholder will have no share of our debt that is recourse to our general partner, but will have a share, generally based on his share of profits, of our non-recourse liabilities. Please read "—Disposition of Common Units—Recognition of Gain or Loss."

        Limitations on Deductibility of Losses.    The deduction by a unitholder of his share of our losses will be limited to the tax basis in his units and, in the case of an individual unitholder or a corporate unitholder, if more than 50% of the value of the corporate unitholder's stock is owned directly or indirectly by or for five or fewer individuals or some tax-exempt organizations, to the amount for which the unitholder is considered to be "at risk" with respect to our activities, if that amount is less than his tax basis. A unitholder subject to these limitations must recapture losses deducted in previous years to the extent that distributions cause his at risk amount to be less than zero at the end of any taxable year. Losses disallowed to a unitholder or recaptured as a result of these limitations will carry forward and will be allowable as a deduction in a later year to the extent that his tax basis or at risk amount, whichever is the limiting factor, is subsequently increased provided that such losses are otherwise allowable. Upon the taxable disposition of a unit, any gain recognized by a unitholder can be offset by losses that were previously suspended by the at risk limitation but may not be offset by losses suspended by the basis limitation. Any excess loss above that gain previously suspended by the at risk or basis limitations is no longer utilizable.

        In general, a unitholder will be at risk to the extent of the tax basis of his units, excluding any portion of that basis attributable to his share of our non-recourse liabilities, reduced by (i) any portion of that basis representing amounts other than were protected against loss because of a guarantee, stop-loss agreement or other similar arrangement and (ii) any amount of money he borrows to acquire or hold his units, if the lender of those borrowed funds owns an interest in us, is related to the unitholder or can look only to the units for repayment. A unitholder's at risk amount will increase or decrease as the tax basis of the unitholder's units increases or decreases, other than tax basis increases or decreases attributable to increases or decreases in his share of our non-recourse liabilities.

        In addition to the basis and at-risk limitations on the deductibility of losses, the passive loss limitations generally provide that individuals, estates, trusts and some closely-held corporations and personal service corporations are permitted to deduct losses from passive activities, which are generally trade or business activities in which the taxpayer does not materially participate, only to the extent of the taxpayer's income from those passive activities. The passive loss limitations are applied separately with respect to each publicly traded partnership. Consequently, any passive losses we generate will only be available to offset our passive income generated in the future and will not be available to offset income from other passive activities or investments, including our investments or investments in other publicly traded partnerships, or a unitholder's salary or active business income. Passive losses that are not deductible because they exceed a unitholder's share of income we generate may be deducted in full when the unitholder disposes of his entire investment in us in a fully taxable transaction with an unrelated party. The passive activity loss limitations are applied after other applicable limitations on deductions, including the at risk rules and the basis limitation.

        A unitholder's share of our net income may be offset by any of our suspended passive losses, but it may not be offset by any other current or carryover losses from other passive activities, including those attributable to other publicly traded partnerships.

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        Limitations on Interest Deductions.    The deductibility of a non-corporate taxpayer's "investment interest expense" is generally limited to the amount of that taxpayer's "net investment income." Investment interest expense includes:

•

interest on indebtedness properly allocable to property held for investment;



•

our interest expense attributed to portfolio income; and



•

the portion of interest expense incurred to purchase or carry an interest in a passive activity to the extent attributable to portfolio income.

        The computation of a unitholder's investment interest expense will take into account interest on any margin account borrowing or other loan incurred to purchase or carry a unit. Net investment income includes gross income from property held for investment and amounts treated as portfolio income under the passive loss rules, less deductible expenses, other than interest, directly connected with the production of investment income, but generally does not include gains attributable to the disposition of property held for investment. The IRS has indicated that net passive income earned by a publicly traded partnership will be treated as investment income to its unitholders for purposes of the investment interest deduction limitation. In addition, the unitholder's share of our portfolio income will be treated as investment income.

        Entity-Level Collections.    If we are required or elect under applicable law to pay any federal, state, local or foreign income tax on behalf of any unitholder or our general partner or any former unitholder, we are authorized to pay those taxes from our funds. That payment, if made, will be treated as a distribution of cash to the unitholder on whose behalf the payment was made. If the payment is made on behalf of a person whose identity cannot be determined, we are authorized to treat the payment as a distribution to all current unitholders. We are authorized to amend the partnership agreement in the manner necessary to maintain uniformity of intrinsic tax characteristics of units and to adjust later distributions, so that after giving effect to these distributions, the priority and characterization of distributions otherwise applicable under the partnership agreement is maintained as nearly as is practicable. Payments by us as described above could give rise to an overpayment of tax on behalf of an individual unitholder in which event the unitholder would be required to file a claim in order to obtain a credit or refund.

        Allocation of Income, Gain, Loss and Deduction.    In general, if we have a net profit, our items of income, gain, loss and deduction will be allocated among our general partner and the unitholders in accordance with their percentage interests in us. At any time that incentive distributions are made to our general partner, gross income will be allocated to the general partner to the extent of these distributions. If we have a net loss for the entire year, that loss will be allocated first to our general partner and the unitholders in accordance with their percentage interests in us to the extent of their positive capital accounts and, second, to our general partner.

        Specified items of our income, gain, loss and deduction will be allocated under Section 704(c) of the Internal Revenue Code to account for the difference between the tax basis and fair market value of our assets at the time of an offering, referred to in this discussion as "Contributed Property." These allocations are required to eliminate the difference between a partner's "book" capital account, credited with the fair market value of Contributed Property, and the "tax" capital account, credited with the tax basis of Contributed Property, referred to in this discussion as the "Book-Tax Disparity." The effect of these allocations to a unitholder purchasing common units from us in an offering will be essentially the same as if the tax basis of Contributed Property was equal to its fair market value at the time of such offering. In the event we issue additional common units or engage in certain other transactions in the future, "reverse Section 704(c) allocations," similar to the Section 704(c) allocations described above, will be made to all persons who are holders of partnership interests immediately prior to such other transaction to account for the difference between the "book" basis for purposes of maintaining capital accounts and the fair market value of all property held by us at the time of the future transaction. In addition, items of recapture income will be allocated to the extent possible to the unitholder who was allocated the deduction giving rise to the treatment of that gain as recapture

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income in order to minimize the recognition of ordinary income by other unitholders. Finally, although we do not expect that our operations will result in the creation of negative capital accounts, if negative capital accounts nevertheless result, items of our income and gain will be allocated in an amount and manner sufficient to eliminate the negative balance as quickly as possible.

        An allocation of items of our income, gain, loss or deduction, other than an allocation required by Section 704(c) to eliminate the Book-Tax Disparity, will generally be given effect for federal income tax purposes in determining a partner's share of an item of income, gain, loss or deduction only if the allocation has substantial economic effect. In any other case, a partner's share of an item will be determined on the basis of his interest in us, which will be determined by taking into account all the facts and circumstances, including:

•

his relative contributions to us;



•

the interests of all the partners in profits and losses;



•

the interest of all the partners in cash flow; and



•

the rights of all the partners to distributions of capital upon liquidation.

        Andrews Kurth LLP is of the opinion that, with the exception of the issues described in "—Tax Consequences of Unit Ownership—Section 754 Election," "—Uniformity of Units" and "—Disposition of Common Units—Allocations Between Transferors and Transferees," allocations under our partnership agreement will be given effect for federal income tax purposes in determining a partner's share of an item of income, gain, loss or deduction.

        Treatment of Short Sales.    A unitholder whose units are loaned to a "short seller" to cover a short sale of units may be considered as having disposed of those units. If so, he would no longer be a partner for tax purposes with respect to those units during the period of the loan and may recognize gain or loss from the disposition. As a result, during this period:

•

any of our income, gain, loss or deduction with respect to those units would not be reportable by the unitholder;



•

any cash distributions received by the unitholder as to those units would be fully taxable; and



•

all of these distributions would appear to be ordinary income.

        Andrews Kurth LLP has not rendered an opinion regarding the treatment of a unitholder where common units are loaned to a short seller to cover a short sale of common units; therefore, unitholders desiring to assure their status as partners and avoid the risk of gain recognition from a loan to a short seller are urged to modify any applicable brokerage account agreements to prohibit their brokers from borrowing and loaning their units. The IRS has announced that it is studying issues relating to the tax treatment of short sales of partnership interests. Please also read "—Disposition of Common Units—Recognition of Gain or Loss."

        Alternative Minimum Tax.    Each unitholder will be required to take into account his distributive share of any items of our income, gain, loss or deduction for purposes of the alternative minimum tax. The current minimum tax rate for non-corporate taxpayers is 26% on the first $175,000 of alternative minimum taxable income in excess of the exemption amount and 28% on any additional alternative minimum taxable income. Prospective unitholders are urged to consult with their tax advisors as to the impact of an investment in units on their liability for the alternative minimum tax.

        Tax Rates.    Under current law, the highest marginal United States federal income tax rate applicable to ordinary income of individuals is 35% and the maximum United States federal income tax rate for net capital gains of an individual is 15% if the asset disposed of was a capital asset held for more than 12 months at the time of disposition. However, absent new legislation extending the current rates, beginning January 1, 2011, the highest marginal U.S. federal income tax rate applicable to

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ordinary income and long-term capital gains of individuals will increase to 39.6% and 20%, respectively. Moreover, these rates are subject to change by new legislation at any time. The recently enacted Health Care and Education Reconciliation Act of 2010 will impose a 3.8% Medicare tax on certain investment income earned by individuals for taxable years beginning after December 31, 2012. For these purposes, investment income generally includes a unitholder's allocable share of our income and gain realized by a unitholder from a sale of units. The tax will be imposed on the lesser of (i) the unitholder's net income from all investments, and (ii) the amount by which the unitholder's adjusted gross income exceeds $250,000 (if the unitholder is married and filing jointly) or $200,000 (if the unitholder is unmarried).

        Section 754 Election.    We have made the election permitted by Section 754 of the Internal Revenue Code. That election is irrevocable without the consent of the IRS. The election generally permits us to adjust a common unit purchaser's tax basis in our assets ("inside basis") under Section 743(b) of the Internal Revenue Code to reflect his purchase price. This election applies to a person who purchases units from a selling unitholder but does not apply to a person who purchases common units directly from us. The Section 743(b) adjustment belongs to the purchaser and not to other unitholders. For purposes of this discussion, a unitholder's inside basis in our assets will be considered to have two components: (1) his share of our tax basis in our assets ("common basis") and (2) his Section 743(b) adjustment to that basis.

        Treasury Regulations under Section 743 of the Internal Revenue Code require, if the remedial allocation method is adopted (which we have adopted), a portion of the Section 743(b) adjustment that is attributable to recovery property subject to depreciation under Section 168 of the Internal Revenue Code to be depreciated over the remaining cost recovery period for the property's unamortized Book-Tax Disparity. Under Treasury Regulation Section 1.167(c)-1(a)(6), a Section 743(b) adjustment attributable to property subject to depreciation under Section 167 of the Internal Revenue Code, rather than cost recovery deductions under Section 168, is generally required to be depreciated using either the straight-line method or the 150% declining balance method. Under our partnership agreement, our general partner is authorized to take a position to preserve the uniformity of units even if that position is not consistent with these and any other Treasury Regulations. Please read "—Uniformity of Units."

        Although Andrews Kurth LLP is unable to opine as to the validity of this approach because there is no controlling authority on this issue, we intend to depreciate the portion of a Section 743(b) adjustment attributable to unrealized appreciation in the value of Contributed Property, to the extent of any unamortized Book-Tax Disparity, using a rate of depreciation or amortization derived from the depreciation or amortization method and useful life applied to the unamortized Book-Tax Disparity of the property, or treat that portion as non-amortizable to the extent attributable to property which is not amortizable. This method is consistent with methods employed by other publicly traded partnerships but is arguably inconsistent with Treasury Regulation Section 1.167(c)-1(a)(6), which is not expected to directly apply to a material portion of our assets. To the extent this Section 743(b) adjustment is attributable to appreciation in value in excess of the unamortized Book-Tax Disparity, we will apply the rules described in the Treasury Regulations and legislative history. If we determine that this position cannot reasonably be taken, we may take a depreciation or amortization position under which all purchasers acquiring units in the same month would receive depreciation or amortization, whether attributable to common basis or a Section 743(b) adjustment, based upon the same applicable rate as if they had purchased a direct interest in our assets. This kind of aggregate approach may result in lower annual depreciation or amortization deductions than would otherwise be allowable to some unitholders. Please read "—Uniformity of Units." A unitholder's tax basis for his common units is reduced by his share of our deductions (whether or not such deductions were claimed on an individual's income tax return) so that any position we take that understates deductions will overstate the common unitholder's basis in his common units, which may cause the unitholder to understate gain or overstate loss on any sale of such units. Please read "—Disposition of Common Units—Recognition of Gain or Loss." The IRS may challenge our position with respect to depreciating or amortizing the Section 743(b) adjustment we take to preserve the uniformity of the units. If such a challenge were sustained, the gain from the sale of units might be increased without the benefit of additional deductions.

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        A Section 754 election is advantageous if the transferee's tax basis in his units is higher than the units' share of the aggregate tax basis of our assets immediately prior to the transfer. In that case, as a result of the election, the transferee would have, among other items, a greater amount of depreciation deductions and his share of any gain or loss on a sale of our assets would be less. Conversely, a Section 754 election is disadvantageous if the transferee's tax basis in his units is lower than those units' share of the aggregate tax basis of our assets immediately prior to the transfer. Thus, the fair market value of the units may be affected either favorably or unfavorably by the election. A basis adjustment is required regardless of whether a Section 754 election is made in the case of a transfer of an interest in us if we have a substantial built-in loss immediately after the transfer, or if we distribute property and have a substantial basis reduction. Generally a basis reduction or a built-in loss is substantial if it exceeds $250,000.

        The calculations involved in the Section 754 election are complex and will be made on the basis of assumptions as to the value of our assets and other matters. For example, the allocation of the Section 743(b) adjustment among our assets must be made in accordance with the Internal Revenue Code. The IRS could seek to reallocate some or all of any Section 743(b) adjustment we allocated to our tangible assets to goodwill instead. Goodwill, an intangible asset, is generally either nonamortizable or amortizable over a longer period of time or under a less accelerated method than our tangible assets. We cannot assure you that the determinations we make will not be successfully challenged by the IRS and that the deductions resulting from them will not be reduced or disallowed altogether. Should the IRS require a different basis adjustment to be made, and should, in our opinion, the expense of compliance exceed the benefit of the election, we may seek permission from the IRS to revoke our Section 754 election. If permission is granted, a subsequent purchaser of units may be allocated more income than he would have been allocated had the election not been revoked.

Tax Treatment of Operations

        Accounting Method and Taxable Year.    We use the year ending December 31 as our taxable year and the accrual method of accounting for federal income tax purposes. Each unitholder will be required to include in income his share of our income, gain, loss and deduction for our taxable year or years ending within or with his taxable year. In addition, a unitholder who has a taxable year different than our taxable year and who disposes of all of his units following the close of our taxable year but before the close of his taxable year must include his share of our income, gain, loss and deduction in income for his taxable year, with the result that he will be required to include in income for his taxable year his share of more than one year of our income, gain, loss and deduction. Please read "—Disposition of Common Units—Allocations Between Transferors and Transferees."

        Tax Basis, Depreciation and Amortization.    We use the tax basis of our assets for purposes of computing depreciation and cost recovery deductions and, ultimately, gain or loss on the disposition of these assets. The federal income tax burden associated with the difference between the fair market value of our assets and their tax basis immediately prior to an offering will be borne by our partners holding interests in us immediately prior to the time we issue units in an offering. Please read "—Tax Consequences of Unit Ownership—Allocation of Income, Gain, Loss and Deduction."

        To the extent allowable, we may elect to use the depreciation and cost recovery methods that will result in the largest deductions being taken in the early years after assets subject to these allowances are placed in-service. Property we subsequently acquire or construct may be depreciated using accelerated methods permitted by the Internal Revenue Code.

        If we dispose of depreciable property by sale, foreclosure or otherwise, all or a portion of any gain, determined by reference to the amount of depreciation previously deducted and the nature of the property, may be subject to the recapture rules and taxed as ordinary income rather than capital gain. Similarly, a unitholder who has taken cost recovery or depreciation deductions with respect to property we own will likely be required to recapture some or all of those deductions as ordinary income upon a sale of his interest in us. Please read "—Tax Consequences of Unit Ownership—Allocation of Income, Gain, Loss and Deduction" and "—Disposition of Common Units—Recognition of Gain or Loss."

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        The costs incurred in selling our units (called "syndication expenses") must be capitalized and cannot be deducted currently, ratably or upon our termination. There are uncertainties regarding the classification of costs as organization expenses, which we may be able to amortize, and as syndication expenses, which we may not amortize. The underwriting discounts and commissions we incur will be treated as syndication expenses.

        Valuation and Tax Basis of Our Properties.    The federal income tax consequences of the ownership and disposition of units will depend in part on our estimates of the relative fair market values, and the tax bases, of our assets. Although we may from time to time consult with professional appraisers regarding valuation matters, we will make many of the relative fair market value estimates ourselves. These estimates and determinations of basis are subject to challenge and will not be binding on the IRS or the courts. If the estimates of fair market value or basis are later found to be incorrect, the character and amount of items of income, gain, loss or deductions previously reported by unitholders might change, and unitholders might be required to adjust their tax liability for prior years and incur interest and penalties with respect to those adjustments.

Disposition of Common Units

        Recognition of Gain or Loss.    Gain or loss will be recognized on a sale of units equal to the difference between the unitholder's amount realized and the unitholder's tax basis for the units sold. A unitholder's amount realized will be measured by the sum of the cash or the fair market value of other property received by him plus his share of our non-recourse liabilities attributable to the common units sold. Because the amount realized includes a unitholder's share of our non-recourse liabilities, the gain recognized on the sale of units could result in a tax liability in excess of any cash received from the sale.

        Prior distributions from us in excess of cumulative net taxable income for a common unit that decreased a unitholder's tax basis in that common unit will, in effect, become taxable income if the common unit is sold at a price greater than the unitholder's tax basis in that common unit, even if the price received is less than his original cost.

        Except as noted below, gain or loss recognized by a unitholder, other than a "dealer" in units, on the sale or exchange of a unit will generally be taxable as capital gain or loss. Capital gain recognized by an individual on the sale of units held more than twelve months will generally be taxed at a maximum U.S. federal income tax rate of 15% through December 31, 2010 and 20% thereafter (absent legislation extending or adjusting the current rate). However, a portion, which will likely be substantial, of this gain or loss will be separately computed and taxed as ordinary income or loss under Section 751 of the Internal Revenue Code to the extent attributable to assets giving rise to depreciation recapture or other "unrealized receivables" or to "inventory items" we own. The term "unrealized receivables" includes potential recapture items, including depreciation recapture. Ordinary income attributable to unrealized receivables, inventory items and depreciation recapture may exceed net taxable gain realized on the sale of a unit and may be recognized even if there is a net taxable loss realized on the sale of a unit. Thus, a unitholder may recognize both ordinary income and a capital loss upon a sale of units. Net capital losses may offset capital gains and no more than $3,000 of ordinary income each year in the case of individuals and may only be used to offset capital gains in the case of corporations.

        The IRS has ruled that a partner who acquires interests in a partnership in separate transactions must combine those interests and maintain a single adjusted tax basis for all those interests. Upon a sale or other disposition of less than all of those interests, a portion of that tax basis must be allocated to the interests sold using an "equitable apportionment" method. Treasury Regulations under Section 1223 of the Internal Revenue Code allow a selling unitholder who can identify common units transferred with an ascertainable holding period to elect to use the actual holding period of the common units transferred. Thus, according to the ruling discussed above, a common unitholder will be unable to select high or low basis common units to sell as would be the case with corporate stock, but, according to the Treasury Regulations, may designate specific common units sold for purposes of determining the holding period of units transferred. A unitholder electing to use the actual holding period of common units transferred must consistently use that identification method for all subsequent

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sales or exchanges of common units. A unitholder considering the purchase of additional units or a sale of common units purchased in separate transactions is urged to consult his tax advisor as to the possible consequences of this ruling and application of the Treasury Regulations.

        Specific provisions of the Internal Revenue Code affect the taxation of some financial products and securities, including partnership interests, by treating a taxpayer as having sold an "appreciated" partnership interest, one in which gain would be recognized if it were sold, assigned or terminated at its fair market value, if the taxpayer or related persons enter(s) into:

•

a short sale;



•

an offsetting notional principal contract; or



•

a futures or forward contract with respect to the partnership interest or substantially identical property.

        Moreover, if a taxpayer has previously entered into a short sale, an offsetting notional principal contract or a futures or forward contract with respect to the partnership interest, the taxpayer will be treated as having sold that position if the taxpayer or a related person then acquires the partnership interest or substantially identical property. The Secretary of the Treasury is also authorized to issue regulations that treat a taxpayer that enters into transactions or positions that have substantially the same effect as the preceding transactions as having constructively sold the financial position.

        Allocations Between Transferors and Transferees.    In general, our taxable income or loss will be determined annually, will be prorated on a monthly basis and will be subsequently apportioned among the unitholders in proportion to the number of units owned by each of them as of the opening of the applicable exchange on the first business day of the month, which we refer to in this prospectus as the "Allocation Date." However, gain or loss realized on a sale or other disposition of our assets other than in the ordinary course of business will be allocated among the unitholders on the Allocation Date in the month in which that gain or loss is recognized. As a result, a unitholder transferring units may be allocated income, gain, loss and deduction realized after the date of transfer.

        Although simplifying conventions are contemplated by the Internal Revenue Code and most publicly traded partnerships use similar simplifying conventions, the use of this method may not be permitted under existing Treasury Regulations. Recently, the Department of the Treasury and the IRS issued proposed Treasury Regulations that provide a safe harbor pursuant to which a publicly traded partnership may use a similar monthly simplifying convention to allocate tax items among transferor and transferee unitholders, although such tax items must be prorated on a daily basis. Existing publicly traded partnerships are entitled to rely on these proposed Treasury Regulations; however, they are not binding on the IRS and are subject to change until final Treasury Regulations are issued. Accordingly, Andrews Kurth LLP is unable to opine on the validity of this method of allocating income and deductions between transferor and transferee unitholders. If this method is not allowed under the Treasury Regulations, or only applies to transfers of less than all of the unitholder's interest, our taxable income or losses might be reallocated among the unitholders. We are authorized to revise our method of allocation between transferor and transferee unitholders, as well as unitholders whose interests vary during a taxable year, to conform to a method permitted under future Treasury Regulations.

        A unitholder who owns units at any time during a quarter and who disposes of them prior to the record date set for a cash distribution for that quarter will be allocated items of our income, gain, loss and deductions attributable to that quarter but will not be entitled to receive that cash distribution.

        Notification Requirements.    A unitholder who sells any of his units, other than through a broker, generally is required to notify us in writing of that sale within 30 days after the sale (or, if earlier, January 15 of the year following the sale). A purchaser of units who purchases units from another unitholder is also generally required to notify us in writing of that purchase within 30 days after the purchase. Upon receiving such notification, we are required to notify the IRS of that transaction and to

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furnish specified information to the transferor and transferee. Failure to notify us of a transfer of units may, in some cases, lead to the imposition of penalties. However, these reporting requirements do not apply to a sale by an individual who is a citizen of the U.S. and who effects the sale or exchange through a broker who will satisfy such requirements.

        Constructive Termination.    We will be considered to have been terminated for tax purposes if there are sales or exchanges which, in the aggregate, constitute 50% or more of the total interests in our capital and profits within a 12-month period. A constructive termination results in the closing of our taxable year for all unitholders. In the case of a unitholder reporting on a taxable year different from our taxable year, the closing of our taxable year may result in more than 12 months of our taxable income or loss being includable in his taxable income for the year of termination. A constructive termination occurring on a date other than December 31 will result in us filing two tax returns (and unitholders could receive two Schedules K-1) for one fiscal year and the cost of the preparation of these returns will be borne by all common unitholders. We would be required to make new tax elections after a termination, including a new election under Section 754 of the Internal Revenue Code, and a termination would result in a deferral of our deductions for depreciation. A termination could also result in penalties if we were unable to determine that the termination had occurred. Moreover, a termination might either accelerate the application of, or subject us to, any tax legislation enacted before the termination. The IRS has recently announced a relief procedure whereby if a publicly traded partnership that has technically terminated requests and is granted relief from the IRS, among other things, the partnership will only have to provide one Schedule K-1 to unitholders for the fiscal year notwithstanding that two partnership tax years result from the termination.

Uniformity of Units

        Because we cannot match transferors and transferees of units, we must maintain uniformity of the economic and tax characteristics of the units to a purchaser of these units. In the absence of uniformity, we may be unable to completely comply with a number of federal income tax requirements, both statutory and regulatory. A lack of uniformity can result from a literal application of Treasury Regulation Section 1.167(c)-1(a)(6). Any non uniformity could have a negative impact on the value of the units. Please read "—Tax Consequences of Unit Ownership—Section 754 Election."

        We depreciate the portion of a Section 743(b) adjustment attributable to unrealized appreciation in the value of Contributed Property, to the extent of any unamortized Book-Tax Disparity, using a rate of depreciation or amortization derived from the depreciation or amortization method and useful life applied to the unamortized Book-Tax Disparity of that property, or treat that portion as nonamortizable, to the extent attributable to property which is not amortizable, consistent with the Treasury Regulations under Section 743 of the Internal Revenue Code, even though that position may be inconsistent with Treasury Regulation Section 1.167(c)-1(a)(6), which is not expected to directly apply to a material portion of our assets. Please read "—Tax Consequences of Unit Ownership—Section 754 Election." To the extent that the Section 743(b) adjustment is attributable to appreciation in value in excess of the unamortized Book-Tax Disparity, we will apply the rules described in the Treasury Regulations and legislative history. If we determine that this position cannot reasonably be taken, we may adopt a depreciation and amortization position under which all purchasers acquiring units in the same month would receive depreciation and amortization deductions, whether attributable to a common basis or Section 743(b) adjustment, based upon the same applicable methods and lives as if they had purchased a direct interest in our property. If this position is adopted, it may result in lower annual depreciation and amortization deductions than would otherwise be allowable to some unitholders and risk the loss of depreciation and amortization deductions not taken in the year that these deductions are otherwise allowable. This position will not be adopted if we determine that the loss of depreciation and amortization deductions will have a material adverse effect on the unitholders. If we choose not to utilize this aggregate method, we may use any other reasonable depreciation and amortization method to preserve the uniformity of the intrinsic tax characteristics of any units that would not have a material adverse effect on the unitholders.

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        Our counsel, Andrews Kurth LLP, is unable to opine on the validity of any of these positions. The IRS may challenge any method of depreciating the Section 743(b) adjustment described in this paragraph. If this challenge were sustained, the uniformity of units might be affected, and the gain from the sale of units might be increased without the benefit of additional deductions. We do not believe these allocations will affect any material items of income, gain, loss or deduction. Please read "—Disposition of Common Units—Recognition of Gain or Loss."

Tax-Exempt Organizations and Other Investors

        Ownership of units by employee benefit plans, other tax-exempt organizations, regulated investment companies, non-resident aliens, foreign corporations and other foreign persons raises issues unique to those investors and, as described below, may have substantially adverse tax consequences to them.

        Employee benefit plans and most other organizations exempt from federal income tax, including individual retirement accounts and other retirement plans, are subject to federal income tax on unrelated business taxable income. Virtually all of our income allocated to a unitholder that is a tax-exempt organization will be unrelated business taxable income and will be taxable to it.

        A regulated investment company or "mutual fund" is required to derive 90% or more of its gross income from certain permitted sources. The American Jobs Creation Act of 2004 generally treats net income from the ownership of publicly traded partnerships as derived from such a permitted source. We anticipate that all of our net income will be treated as derived from such a permitted source.

        Non-resident aliens and foreign corporations, trusts or estates that own units will be considered to be engaged in business in the U.S. because of the ownership of units. As a consequence, they will be required to file federal tax returns to report their share of our income, gain, loss or deduction and pay federal income tax at regular rates on their share of our net income or gain. Moreover, under rules applicable to publicly traded partnerships, we will withhold tax at the highest applicable effective tax rate from cash distributions made quarterly to foreign unitholders. Each foreign unitholder must obtain a taxpayer identification number from the IRS and submit that number to our transfer agent on a Form W-8BEN or applicable substitute form in order to obtain credit for these withholding taxes. A change in applicable law may require us to change these procedures.

        In addition, because a foreign corporation that owns units will be treated as engaged in a U.S. trade or business, that corporation may be subject to the U.S. branch profits tax at a rate of 30%, in addition to regular federal income tax, on its share of our income and gain, as adjusted for changes in the foreign corporation's "U.S. net equity," that is effectively connected with the conduct of a U.S. trade or business. That tax may be reduced or eliminated by an income tax treaty between the U.S. and the country in which the foreign corporate unitholder is a "qualified resident." In addition, this type of unitholder is subject to special information reporting requirements under Section 6038C of the Internal Revenue Code.

        Under a ruling published by the IRS, a foreign unitholder who sells or otherwise disposes of a unit will be subject to federal income tax on gain realized on the sale or disposition of that unit to the extent that this gain is effectively connected with a U.S. trade or business of the foreign unitholder. Because a foreign unitholder is considered to be engaged in a trade or business in the U.S. by virtue of the ownership of the common units, under this ruling, a foreign unitholder who sells or otherwise disposes of a unit generally will be subject to federal income tax on gain realized on the sale or other disposition of the common units. Apart from the ruling, a foreign unitholder will not be taxed or subject to withholding upon the sale or disposition of a unit if he has owned less than 5% in value of the units during the five-year period ending on the date of the disposition and if the units are regularly traded on an established securities market at the time of the sale or disposition.

Administrative Matters

        Information Returns and Audit Procedures.    We intend to furnish to each unitholder, within 90 days after the close of each taxable year, specific tax information, including a Schedule K-1, which describes

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each unitholder's share of our income, gain, loss and deduction for our preceding taxable year. In preparing this information, which will not be reviewed by counsel, we will take various accounting and reporting positions, some of which have been mentioned earlier, to determine each unitholder's share of income, gain, loss and deduction. We cannot assure you that those positions will in all cases yield a result that conforms to the requirements of the Internal Revenue Code, Treasury Regulations or administrative interpretations of the IRS. Neither we nor Andrews Kurth LLP can assure prospective unitholders that the IRS will not successfully contend in court that those positions are impermissible. Any challenge by the IRS could negatively affect the value of the units.

        The IRS may audit our federal income tax information returns. Adjustments resulting from an IRS audit may require each unitholder to adjust a prior year's tax liability, and possibly may result in an audit of his return. Any audit of a unitholder's return could result in adjustments not related to our returns as well as those related to our returns.

        Partnerships generally are treated as separate entities for purposes of federal income tax audits, judicial review of administrative adjustments by the IRS and tax settlement proceedings. The tax treatment of partnership items of income, gain, loss and deduction is determined in a partnership proceeding rather than in separate proceedings with the partners. The Internal Revenue Code requires that one partner be designated as the "Tax Matters Partner" for these purposes. The partnership agreement names our general partner as our Tax Matters Partner.

        The Tax Matters Partner has made and will make some elections on our behalf and on behalf of unitholders. In addition, the Tax Matters Partner can extend the statute of limitations for assessment of tax deficiencies against unitholders for items in our returns. The Tax Matters Partner may bind a unitholder with less than a one percent profits interest in us to a settlement with the IRS unless that unitholder elects, by filing a statement with the IRS, not to give that authority to the Tax Matters Partner. The Tax Matters Partner may seek judicial review, by which all the unitholders are bound, of a final partnership administrative adjustment and, if the Tax Matters Partner fails to seek judicial review, judicial review may be sought by any unitholder having at least a 1% interest in profits or by any group of unitholders having in the aggregate at least a 5% interest in profits. However, only one action for judicial review will go forward, and each unitholder with an interest in the outcome may participate in that action.

        A unitholder must file a statement with the IRS identifying the treatment of any item on his federal income tax return that is not consistent with the treatment of the item on our return. Intentional or negligent disregard of this consistency requirement may subject a unitholder to substantial penalties.

        Nominee Reporting.    Persons who hold an interest in us as a nominee for another person are required to furnish the following information to us:

        (a)   the name, address and taxpayer identification number of the beneficial owner and the nominee;

        (b)   a statement regarding whether the beneficial owner is:

        1.     a person that is not a U.S. person;

        2.     a foreign government, an international organization or any wholly owned agency or instrumentality of either of the foregoing; or

        3.     a tax-exempt entity;

        (c)   the amount and description of units held, acquired or transferred for the beneficial owner; and

        (d)   specific information including the dates of acquisitions and transfers, means of acquisitions and transfers, and acquisition cost for purchases, as well as the amount of net proceeds from sales.

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        Brokers and financial institutions are required to furnish additional information, including whether they are U.S. persons and specific information on units they acquire, hold or transfer for their own account. A penalty of $50 per failure, up to a maximum of $100,000 per calendar year, is imposed by the Internal Revenue Code for failure to report that information to us. The nominee is required to supply the beneficial owner of the units with the information furnished to us.

        Accuracy-Related Penalties.    An additional tax equal to 20% of the amount of any portion of an underpayment of tax that is attributable to one or more specified causes, including negligence or disregard of rules or regulations, substantial understatements of income tax and substantial valuation misstatements, is imposed by the Internal Revenue Code. No penalty will be imposed, however, for any portion of an underpayment if it is shown that there was a reasonable cause for the underpayment of that portion and that the taxpayer acted in good faith regarding the underpayment of that portion.

        For individuals, a substantial understatement of income tax in any taxable year exists if the amount of the understatement exceeds the greater of 10% of the tax required to be shown on the return for the taxable year or $5,000. The amount of any understatement subject to penalty generally is reduced if any portion is attributable to a position adopted on the return:

        (1)   for which there is, or was, "substantial authority"; or

        (2)   as to which there is a reasonable basis if the pertinent facts of that position are adequately disclosed on the return.

        If any item of income, gain, loss or deduction included in the distributive shares of unitholders might result in that kind of an "understatement" of income for which no "substantial authority" exists, we must disclose the pertinent facts on our return. In addition, we will make a reasonable effort to furnish sufficient information for unitholders to make adequate disclosure on their returns to avoid liability for this penalty. More stringent rules apply to "tax shelters," but we believe we are not a tax shelter.

        A substantial valuation misstatement exists if (a) the value of any property, or the adjusted basis of any property, claimed on a tax return is 150% or more of the amount determined to be the correct amount of the valuation or adjusted basis, (b) the price for any property or services (or for the use of property) claimed on any such return with respect to any transaction between persons described in Internal Revenue Code Section 482 is 200% or more (or 50% or less) of the amount determined under Section 482 to be the correct amount of such price, or (c) the net Internal Revenue Code Section 482 transfer price adjustment for the taxable year exceeds the lesser of $5 million or 10% of the taxpayer's gross receipts.

        No penalty is imposed unless the portion of the underpayment attributable to a substantial valuation misstatement exceeds $5,000 ($10,000 for most corporations). If the valuation claimed on a return is 200% or more than the correct valuation, the penalty imposed increases to 40%. We do not anticipate making any valuation misstatements.

        Reportable Transactions.    If we were to engage in a "reportable transaction," we (and possibly you and others) would be required to make a detailed disclosure of the transaction to the IRS. A transaction may be a reportable transaction based upon any of several factors, including the fact that it is a type of tax avoidance transaction publicly identified by the IRS as a "listed transaction" or a "transaction of interest" or that it produces certain kinds of losses in excess of $2 million in any single year, or $4 million in any combination of six successive tax years. Our participation in a reportable transaction could increase the likelihood that our federal income tax information return (and possibly your tax return) would be audited by the IRS. Please read "—Information Returns and Audit Procedures" above.

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        Moreover, if we were to participate in a reportable transaction with a significant purpose to avoid or evade tax, or in any listed transaction, you may be subject to the following provisions of the American Jobs Creation Act of 2004:

•

accuracy-related penalties with a broader scope, significantly narrower exceptions, and potentially greater amounts than described above at "—Accuracy-Related Penalties,"



•

for those persons otherwise entitled to deduct interest on federal tax deficiencies, nondeductibility of interest on any resulting tax liability, and



•

in the case of a listed transaction, an extended statute of limitations.

        We do not expect to engage in any "reportable transactions."

        Registration as a Tax Shelter.    We registered as a "tax shelter" under the law in effect at the time of our initial public offering and were assigned a tax shelter registration number. Issuance of a tax shelter registration number to us does not indicate that investment in us or the claimed tax benefits have been reviewed, examined or approved by the IRS. The term "tax shelter" has a different meaning for this purpose than under the penalty rules described above at "—Accuracy-Related Penalties."

State, Local, Foreign and Other Tax Considerations

        In addition to federal income taxes, you likely will be subject to other taxes, such as state, local and foreign income taxes, unincorporated business taxes, and estate, inheritance or intangible taxes that may be imposed by the various jurisdictions in which we do business or own property or in which you are a resident. Although an analysis of those various taxes is not presented here, each prospective unitholder should consider their potential impact on his investment in us. Although you may not be required to file a return and pay taxes in some jurisdictions if your income from that jurisdiction falls below the filing and payment requirement, you will be required to file income tax returns and to pay income taxes in many other jurisdictions in which we do business or own property and may be subject to penalties for failure to comply with those requirements. In some jurisdictions, tax losses may not produce a tax benefit in the year incurred and may not be available to offset income in subsequent taxable years. Some of the jurisdictions may require us, or we may elect, to withhold a percentage of income from amounts to be distributed to a unitholder who is not a resident of the jurisdiction. Withholding, the amount of which may be greater or less than a particular unitholder's income tax liability to the jurisdiction, generally does not relieve a nonresident unitholder from the obligation to file an income tax return. Amounts withheld will be treated as if distributed to unitholders for purposes of determining the amounts distributed by us. Please read "—Tax Consequences of Unit Ownership—Entity-Level Collections." Based on current law and our estimate of our future operations, our general partner anticipates that any amounts required to be withheld will not be material.

        It is the responsibility of each unitholder to investigate the legal and tax consequences, under the laws of pertinent jurisdictions, of his investment in us. Accordingly, each prospective unitholder is urged to consult, and depend on, his own tax counsel or other advisor with regard to those matters. Further, it is the responsibility of each unitholder to file all state, local and foreign tax returns, as well as U.S. federal tax returns, that may be required of him. Andrews Kurth LLP has not rendered an opinion on the state, local or foreign tax consequences of an investment in us.

Tax Consequences of Ownership of Debt Securities

        A description of the material federal income tax consequences of the acquisition, ownership and disposition of debt securities will be set forth in the prospectus supplement relating to the offering of debt securities.

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INVESTMENT IN NUSTAR ENERGY BY EMPLOYEE BENEFIT PLANS

        An investment in us by an employee benefit plan is subject to additional considerations to the extent that the investments by these plans are subject to the fiduciary responsibility and prohibited transaction provisions of ERISA, and restrictions imposed by Section 4975 of the Internal Revenue Code. For these purposes, the term "employee benefit plan" includes, but is not limited to, certain qualified pension, profit-sharing and stock bonus plans, Keogh plans, simplified employee pension plans and individual retirement annuities or accounts (IRAs) established or maintained by an employer or employee organization. Incident to making an investment in us, among other things, consideration should be given by an employee benefit plan to:

•

whether the investment is prudent under Section 404(a)(1)(B) of ERISA;



•

whether in making the investment, that plan will satisfy the diversification requirements of Section 404(a)(l)(C) of ERISA; and



•

whether the investment will result in recognition of unrelated business taxable income by the plan and, if so, the potential after-tax investment return.

        In addition, the person with investment discretion with respect to the assets of an employee benefit plan or other arrangement that is covered by the prohibited transactions restrictions of the Internal Revenue Code, often called a fiduciary, should determine whether an investment in us is authorized by the appropriate governing instrument and is a proper investment for the plan or arrangement.

        Section 406 of ERISA and Section 4975 of the Internal Revenue Code prohibit certain employee benefit plans, and Section 4975 of the Internal Revenue Code prohibits IRAs and certain other arrangements that are not considered part of an employee benefit plan, from engaging in specified transactions involving "plan assets" with parties that are "parties in interest" under ERISA or "disqualified persons" under the Internal Revenue Code with respect to the plan or other arrangement that is covered by ERISA or the Internal Revenue Code.

        The U.S. Department of Labor regulations provide guidance with respect to whether the assets of an entity in which employee benefit plans or other arrangements described above acquire equity interests would be deemed "plan assets" under some circumstances. Under these regulations, an entity's assets would not be considered to be "plan assets" if, among other things:

•

the equity interests acquired by employee benefit plans or other arrangements described above are publicly offered securities; i.e., the equity interests are widely held by 100 or more investors independent of the issuer and each other, freely transferable and registered under some provisions of the federal securities laws;



•

the entity is an "operating company,"—i.e., it is primarily engaged in the production or sale of a product or service other than the investment of capital either directly or through a majority owned subsidiary or subsidiaries; or



•

less than 25% of the value of each class of equity interest, disregarding any such interests held by our general partner, its affiliates, and some other persons, is held by the employee benefit plans referred to above, IRAs and other employee benefit plans or arrangements subject to ERISA or Section 4975 of the Code.

        Our assets should not be considered "plan assets" under these regulations because the investment in our common stock will satisfy the requirements in the first bullet point above.

        Plan fiduciaries contemplating a purchase of common stock should consult with their own counsel regarding the consequences of such purchase under ERISA and the Internal Revenue Code in light of possible personal liability for any breach of fiduciary duties and the imposition of serious penalties on persons who engage in prohibited transactions under ERISA or the Internal Revenue Code.

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LEGAL MATTERS

        The validity of the securities, as to matters of United States law and other customary legal matters relating to the offering the securities issued by us, will be passed upon for us by Andrews Kurth LLP, Houston, Texas. If the securities are being distributed through underwriters or agents, the validity of the securities will be passed upon for the underwriters or agents by counsel identified in the related prospectus supplement.

EXPERTS

        The consolidated financial statements of NuStar Energy L.P. as of December 31, 2009, 2008 and 2007, and for each of the years in the three-year period ended December 31, 2009, and management's assessment of the effectiveness of internal control over financial reporting as of December 31, 2009, and the balance sheets of NuStar GP Holdings, LLC as of December 31, 2009 and 2008, included as Exhibit 99.02 to NuStar Energy L.P.'s Annual Report on Form 10-K for the year ended December 31, 2009, have been incorporated by reference herein in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

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Joint Book-Running Managers

 

Co-Managers

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