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TABLE OF CONTENTS

Table of Contents

As filed with the Securities and Exchange Commission on May 19, 2015

Registration No. 333-                


UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549



FORM S-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933



CLEAN DIESEL TECHNOLOGIES, INC.
(Exact Name of Registrant as Specified in its Charter)



Delaware
(State or Other Jurisdiction of
Incorporation or Organization)
  3564
(Primary Standard Industrial
Classification Code Number)
  06-1393453
(I.R.S. Employer
Identification No.)

1621 Fiske Place
Oxnard, CA 93033
(805) 639-9458
(Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant's Principal Executive Offices)



David E. Shea
Chief Financial Officer
Clean Diesel Technologies, Inc.
1621 Fiske Place
Oxnard, CA 93033
(805) 639-9467
(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent for Service)



Copy to:

Steven D. Pidgeon
DLA Piper LLP (US)
2525 East Camelback Road, Suite 1000
Phoenix, AZ 85016-4232
480-606-5124



Approximate Date of Commencement of Proposed sale to the Public:
From time to time after this registration statement becomes effective.

               If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box:    o

               If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or reinvestment plans, check the following box:    ý

               If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering:    o

               If this form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering:    o

               If this form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box:    o

               If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box:    o

               Indicate by checkmark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company (as defined in Rule 12b-2 of the Exchange Act).

Large accelerated filer o   Accelerated filer o   Non-accelerated filer o   Smaller reporting company ý



CALCULATION OF REGISTRATION FEE

       
 
Title of Each Class of Securities
to be Registered(1)

  Proposed Maximum
Aggregate Offering
Price(1)(2)

  Amount of
Registration Fee(2)(3)

 

Common Stock, par value $0.01 per share(4)

       
 

Preferred Stock, par value $0.01 per share(5)

       
 

Warrants(6)

       
 

Units(7)

       
 

Total

  $50,000,000   $2,228

 

(1)
There are being registered an indeterminate number of securities as shall have an aggregate offering price not to exceed $50,000,000 (consisting of newly registered securities and securities carried over from a prior registration statement, as discussed in footnote 2). The securities registered hereunder may be sold separately or with other securities registered hereunder. The proposed maximum aggregate offering price per class of security will be determined from time to time by the registrant in connection with the issuance by the registrant of the securities registered under this registration statement and is not specified as to each class of security being registered under this registration statement pursuant to General Instruction II.D. of Form S-3 under the Securities Act of 1933, as amended (the "Securities Act"). In addition, pursuant to Rule 416 of the rules and regulations under the Securities Act, the securities being registered hereunder include such indeterminate number of shares of common stock and preferred stock as may be issuable with respect to the securities being registered hereunder as a result of stock splits, stock dividends or similar transactions. Separate consideration may or may not be received for securities that are issuable on exercise, conversion or exchange of other securities or that are issued in units.

(2)
Pursuant to Rule 415(a)(6) under the Securities Act, the securities registered pursuant to this registration statement include unsold securities previously registered by the registrant on the registrant's registration statement (File No. 333-181443) filed on May 15, 2012 and declared effective on May 21, 2012 (the "2012 Registration Statement"). The 2012 Registration Statement registered the offer and sale of an indeterminate number of shares of common stock, an indeterminate number of shares of preferred stock, an indeterminate number of warrants to purchase common stock or preferred stock, and an indeterminate number of units comprised of shares of common stock or preferred stock and warrants to purchase common stock or preferred stock or any combination, having an aggregate initial offering price of $50,000,000, a portion which remain unsold as of the date of filing this registration statement. The registrant has determined to include in this registration statement certain unsold securities under the 2012 Registration Statement with an aggregate offering price of $30,831,573.95 (the "Unsold Securities"). Pursuant to Rule 415(a)(6) under the Securities Act, the filing fee of $3,533.30 relating to the Unsold Securities under the 2012 Registration Statement will continue to be applied to the Unsold Securities registered pursuant to this registration statement. The registrant is also registering new securities on this registration statement with an aggregate initial offering price of $19,168,426.05 (the "New Securities"), which aggregate offering price is not specified as to each class of security (see footnote (1)). The proposed maximum aggregate offering price has been estimated solely for the purpose of calculating the registration fee in accordance with Rule 457(o) under the Securities Act and corresponds to the New Securities being registered hereby and not to the Unsold Securities carried over from the 2012 Registration Statement. To the extent that, after the filing date hereof and prior to the effectiveness of this registration statement, the registrant sells any Unsold Securities pursuant to the 2012 Registration Statement, the registrant will identify in a pre-effective amendment to this registration statement the updated amount of Unsold Securities from the 2012 Registration Statement to be included in this registration statement pursuant to Rule 415(a)(6) and the updated amount of New Securities to be registered on this registration statement. Pursuant to Rule 415(a)(6) under the Securities Act, the offering of the Unsold Securities under the 2012 Registration Statement will be deemed terminated as of the date of effectiveness of this registration statement.

(3)
The total filing fee of $2,228.00 paid by the Registrant in connection with this registration statement corresponds to the registration of the New Securities and not the Unsold Securities in accordance with Rule 415(a)(6). See also footnote (2) above.

(4)
Subject to footnote 1 above, there is being registered hereunder an indeterminate number of shares of common as may be sold from time to time, at indeterminate prices, by the registrant.

(5)
Subject to footnote 1 above, there is being registered hereunder an indeterminate number of shares of preferred stock (with accompanying purchase rights, if any) as may be sold from time to time, at indeterminate prices, by the registrant. In addition, the securities being registered in this registration statement also consist of such an indeterminate amount of common stock (with accompanying purchase rights, if any) (i) as may be issuable or deliverable upon conversion of shares of preferred stock, and (ii) as may be required for delivery upon conversion of shares of preferred stock as a result of anti-dilution provisions.

(6)
Subject to footnote 1 above, there is being registered hereunder an indeterminate number of warrants to purchase common stock or preferred stock of one or more series registered under this registration statement as may be sold from time to time, at indeterminate prices, by the registrant. In addition, the securities being registered in this registration statement also consist of such an indeterminate amount of common stock and preferred stock (in each case, with accompanying purchase rights, if any) (i) as may be issuable or deliverable upon exercise of warrants and (ii) as may be required for delivery upon exercise of any warrants as a result of anti-dilution provisions.

(7)
Subject to footnote 1 above, there is being registered hereunder an indeterminate number of units , consisting of one or more shares of common stock, shares of preferred stock, warrants, or any combination of such securities, as may be sold from time to time, at indeterminate prices, by the registrant.



               The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

   


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The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

Subject to Completion, Dated May 19, 2015

PROSPECTUS

CLEAN DIESEL TECHNOLOGIES, INC.

LOGO

$50,000,000
Common Stock
Preferred Stock
Warrants
Units



        By this prospectus, we may offer and sell from time to time up to $50,000,000 in total of any combination of the securities described in this prospectus, either individually or in units. We may also offer common stock upon conversion of preferred stock or common stock or preferred stock upon the exercise of warrants. This prospectus provides a general description of securities we may offer. Each time we offer securities, we will provide a prospectus supplement containing more information about the particular offering together with this prospectus. The prospectus supplement also may add, update or change information contained in this prospectus. This prospectus may not be used to offer and sell securities without a prospectus supplement.

        The securities may be sold directly by us to investors, through agents designated from time to time or to or through underwriters or dealers, on a delayed or continuous basis. For additional information on the methods of sale, you should refer to the section entitled "Plan of Distribution" in this prospectus. If any agents or underwriters are involved in the sale of any securities, the names of such agents or underwriters and any applicable fees, commissions, discounts and over-allotment options will be set forth in the applicable prospectus supplement.

        Our common stock is listed on the NASDAQ Capital Market under the symbol "CDTI." On May 18, 2015, the last reported sale price of our common stock was $2.09 per share. Pursuant to General Instruction I.B.6 of Form S-3, as long as the aggregate market value of our common stock held by non-affiliates remains below $75.0 million, we will not, during any 12 calendar month period, sell the securities in a public primary offering with a value exceeding more than one-third of the aggregate market value of our common stock held by non-affiliates. As of April 30, 2015, the aggregate market value of our outstanding common stock held by non-affiliates was approximately $31,040,790, which was calculated based on 13,982,338 shares of outstanding common stock held by non-affiliates and a price per share of $2.22, the last reported sale price per share of our common stock on the NASDAQ Capital Market on May 14, 2015. We have offered securities for an aggregate market value of $5,185,259.90 during the 12 calendar months preceding and including the date hereof pursuant to General Instruction I.B.6 of Form S-3.

        Investing in our securities involves a high degree of risk. We refer you to the section entitled "Risk Factors" on page 3 of this prospectus and in the applicable prospectus supplement and under similar sections in the documents we incorporate by reference into this prospectus.

        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                        , 2015


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TABLE OF CONTENTS

ABOUT THIS PROSPECTUS

    1  

ABOUT OUR COMPANY

    1  

RISK FACTORS

    3  

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

    3  

USE OF PROCEEDS

    3  

DILUTION

    4  

RATIO OF EARNINGS TO FIXED CHARGES

    4  

DESCRIPTION OF COMMON STOCK

    4  

DESCRIPTION OF PREFERRED STOCK

    7  

DESCRIPTION OF WARRANTS

    8  

DESCRIPTION OF UNITS

    11  

PLAN OF DISTRIBUTION

    12  

LEGAL MATTERS

    15  

EXPERTS

    16  

WHERE YOU CAN FIND MORE INFORMATION

    16  

INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

    16  

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ABOUT THIS PROSPECTUS

        This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission ("SEC") using a "shelf" registration process. Under this shelf registration process, we may offer to sell any one or more or a combination of the securities described in this prospectus in one or more offerings up to a total dollar amount of $50,000,000 (or its equivalent based on the applicable exchange rate at the time of the sale in one or more foreign currencies, currency units or composite currencies that we may designate). We have provided to you in this prospectus 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. We also may add, update or change in the prospectus supplement any of the information contained in this prospectus. If there is an inconsistency between the information in this prospectus and a prospectus supplement, you should rely on the information in the prospectus supplement. You should read carefully both this prospectus and the applicable prospectus supplement together with the documents we incorporate by reference into this prospectus as described under the heading "Incorporation of Certain Documents By Reference" before making an investment decision. THIS PROSPECTUS MAY NOT BE USED TO OFFER AND SELL SECURITIES WITHOUT A PROSPECTUS SUPPLEMENT.

        The registration statement that contains this prospectus, including the exhibits to the registration statement and the information incorporated by reference, provides additional information about the securities offered under this prospectus. That registration statement can be read at the SEC web site or at the SEC public reference room as discussed under the heading "Where You Can Find More Information."

        You should rely only on the information provided in this prospectus and in any prospectus supplement, including the information incorporated by reference. We have not authorized anyone to provide you with different information. You should not assume that the information in this prospectus or any supplement to this prospectus is accurate at any date other than the date indicated on the cover page of these documents. We are not making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted.

        In this prospectus, references to "Clean Diesel Technologies," "Clean Diesel," "CDTI," the "company," "we," "our" or "us," unless the context otherwise requires, refer to Clean Diesel Technologies, Inc.


ABOUT OUR COMPANY

        Our business is evolving from being a niche manufacturer of emissions control solutions for the motor vehicle OEM, retrofit and aftermarket markets to becoming an advanced materials technology provider for these markets. Our advanced materials technology is comprised of our low platinum group metal, or PGM, catalysts, including synergized-PGM, or SPGM™, and our zero-PGM, or ZPGM™, catalysts. Recently, we announced that testing was underway for new generation catalyst technologies, including our Spinel™ technology, which is a platform based on proprietary materials incorporating various base metals that replace costly PGMs and rare earth metals in coatings on vehicle catalytic converters. Once verified, we intend to commercialize our new catalyst technologies by supplying proprietary powders and/or licenses to other vehicle catalyst manufacturers, as well as manufacturing catalysts for select customers in our existing facilities. We believe that this business model will allow us to achieve greater scale and higher return on our technology investment than in the past. Recent preliminary engine and vehicle test results for our SPGM™ diesel oxidation catalyst, or DOC, technology indicate the achievement of emission control and system performance comparable to a leading OEM catalyst product while reducing PGM usage by over 80%.

        We currently commercialize our materials technology by manufacturing and distributing light duty vehicle catalysts and heavy duty diesel emissions control systems and products to major automakers,

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distributors, integrators and retrofitters. We have more than 14 years history of supplying catalysts to light duty vehicle OEMs and 35 years of experience in the heavy duty diesel systems market. We have a proven technical and manufacturing competence in the light duty vehicle catalyst market meeting auto makers' stringent requirements for performance, quality and delivery. Our business is driven by increasingly stringent global emission standards for internal combustion engines, which are major sources of a variety of harmful pollutants. Since inception, we have developed a substantial portfolio of patents and related proprietary rights and extensive technological know-how.

        We organize our operations in two business divisions: Catalyst and Heavy Duty Diesel Systems.

        Catalyst.    Utilizing our advanced materials technology platform, we develop and produce catalysts to reduce emissions from gasoline, diesel and natural gas combustion engines. Most catalytic systems require significant amounts of costly PGMs to operate efficiently. Using our proprietary mixed-phase catalyst, or MPC®, technology, we have developed a family of unique high-performance catalysts, featuring inexpensive base-metals with low or even no PGM content. We expect that our next-generation technologies will enable further advances in catalyst performance and further reductions in PGM usage. Our technical and manufacturing capabilities have been established to meet automakers' most stringent requirements. Since 2001, we have supplied over eleven million parts to light duty vehicle OEM customers. Our Catalyst division is also a supplier of products for our Heavy Duty Diesel Systems division.

        Heavy Duty Diesel Systems.    We specialize in the design and manufacture of verified exhaust emissions control solutions, and we offer a full range of products for the verified retrofit and non-retrofit OEM and aftermarket markets through our distribution/dealer network and direct sales. We believe we offer one of the industry's most comprehensive portfolios of emissions control systems for use in engine retrofit programs that have been evaluated and verified as compliant with applicable regulations by the United States, or U.S., Environmental Protection Agency, or EPA, and the California Air Resources Board, or CARB, as well as by regulators in several European countries. Recently, we launched our DuraFit™ OEM replacement diesel particulate filters, which leverage our proprietary catalyst technology within the medium and heavy duty vehicle parts replacement market, a new market segment for us. Sales of emissions control systems by our Heavy Duty Diesel Systems division are driven by the regulation of diesel emissions, particularly in the State of California.

        We are headquartered, in Oxnard, California and have operations in the United States, Canada, the United Kingdom, France, Japan and Sweden. We also have an Asian investment. Our proprietary catalyst products are manufactured at our facility in Oxnard, California and our heavy duty diesel systems and products are manufactured at our facilities in Thornhill, Canada and Malmö, Sweden. Our principal executive offices are located at 1621 Fiske Place, Oxnard, California 93033 and our telephone number at that location is (805) 639-9458. We maintain an Internet website at www.cdti.com. Information contained in or accessible through our website does not constitute part of this prospectus.

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RISK FACTORS

        An investment in our securities involves a high degree of risk. You should carefully consider the risk factors described in Part I, Item 1A, "Risk Factors" in our Annual Report on Form 10-K for the fiscal year ended December 31, 2014, as well as the risks, uncertainties and additional information set forth in the other documents incorporated by reference in this prospectus. For a description of these reports and documents, and information about where you can find them, see "Where You Can Find More Information" and "Incorporation of Certain Documents by Reference." Before making any investment decision, you should carefully consider these risks as well as other information we include or incorporate by reference in this prospectus or in any applicable prospectus supplement. The risks and uncertainties described in the prospectus supplement and the documents we incorporate by reference into this prospectus are not the only ones we face. Additional risks and uncertainties that we are unaware of or that we believe are not material at the time could also materially adversely affect our business, financial condition or results of operations. In any case, the value of our securities could decline, and you could lose all or part of your investment. See also the information contained under the heading "Cautionary Statement Regarding Forward-Looking Statements" immediately below.


CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

        This prospectus and the information incorporated by reference in this prospectus include "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933, as amended, (the "Securities Act"), and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). Without limiting the foregoing, the words "may," "believe," "may," "could," "might," "possible," "potential," "project," "will," "should," "expect," "intend," "plan," "predict," "anticipate," "estimate," "approximate," "contemplate" or "continue" "target," "goal" and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these words. All forward-looking statements included in this prospectus are based on information available to us up to, and including, the date of this document, and we assume no obligation to update any such forward-looking statements to reflect events or circumstances that arise after the date hereof. Our actual results could differ materially from those anticipated in these forward-looking statements as a result of certain important factors, including those contained in or incorporated by reference into this prospectus. You should carefully review those factors and also carefully review the risks outlined in other documents that we file from time to time with the SEC.


USE OF PROCEEDS

        We will retain broad discretion over the use of net proceeds to us from the sale of our securities offered hereby. Except as may be otherwise described in a prospectus supplement, we currently anticipate using any net proceeds to us for general corporate purposes, which may include working capital, general and administrative expenses, capital expenditures and implementation of our strategic priorities. We may also use a portion of the net proceeds to acquire or invest in businesses, products and technologies that are complementary to our current business, although we have no present commitments or agreements for any such transactions. The amounts and timing of our actual expenditures for each purpose may vary significantly depending upon numerous factors, including the actual amount of proceeds we receive, competition and economic or other conditions.

        We cannot guarantee that we will receive any proceeds in connection with any offering hereunder because we may choose not to issue any of the securities covered by this prospectus. If we choose to issue securities, we will provide a prospectus supplement that will contain information about how we intend to use the proceeds from each such offering.

        Pending the application of such proceeds, we may invest the proceeds in short-term, interest bearing, investment-grade marketable securities or money market obligations.

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DILUTION

        If there is a material dilution of the purchasers' equity interest from the sale of common equity securities offered under this prospectus, we will set forth in any prospectus supplement the following information regarding any such material dilution:


RATIO OF EARNINGS TO FIXED CHARGES

        Because we have no preferred stock issued (and have not had any issued during the last five fiscal years), a ratio of earnings to combined fixed charges and preferred dividends is not presented. If we issue preferred stock in the future, we will set forth in any prospectus supplement the ratio of earnings to combined fixed charges and preferred dividends for the last five fiscal years.


DESCRIPTION OF COMMON STOCK

        The following description of our common stock, together with the additional information we include in any applicable prospectus supplement, summarizes the material terms and provisions of our common stock that we may offer under this prospectus. For the complete terms of our common stock, please refer to our Restated Certificate of Incorporation ("Certificate of Incorporation") and Bylaws, in each case as amended. The description herein does not contain all of the information that you may find useful or that may be important to you. You should refer to the provisions of our Certificate of Incorporation and Bylaws because they, and not the summary, define the rights of holders of shares of our common stock. You can obtain copies of our Certificate of Incorporation and Bylaws by following the directions under the heading "Where You Can Find More Information." The terms of our common stock also may be affected by Delaware law.

Authorized and Outstanding Capital Stock

        We are authorized to issue 24,000,000 shares of common stock, $0.01 par value per share. As of May 11, 2015, we had 14,194,702 shares of common stock outstanding. In addition, we had 1,610,069 shares of common stock reserved for issuance under outstanding warrants; 412,923 shares reserved for issuance under outstanding stock options; 243,873 shares reserved for issuance under outstanding restricted stock units; 250,000 shares reserved for issuance under convertible notes; and 180,538 shares reserved for issuance under our equity incentive plan. As of the date of this prospectus, we do not have any shares of preferred stock outstanding.

Voting Rights

        For all matters submitted to a vote of stockholders, each holder of common stock is entitled to one vote for each share registered in the holder's name on our books. Our common stock does not have cumulative voting rights. The holders of a plurality of the shares of our common stock entitled to vote in any election of directors, voting together as a single class, can elect all of the directors standing for election, if they so choose.

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Dividends

        Subject to limitations under Delaware law and preferences that may be applicable to any then outstanding preferred stock, holders of common stock are entitled to receive ratably those dividends, if any, as may be declared by our Board of Directors out of legally available funds. We have never paid any cash dividends on our common stock and do not anticipate paying dividends in the near future.

Liquidation

        Upon our liquidation, dissolution or winding up, the holders of common stock will be entitled to share ratably in the net assets legally available for distribution to stockholders after the payment of all of our debts and other liabilities of our company, subject to the prior rights of any preferred stock then outstanding.

Fully Paid and Nonassessable

        All shares of our outstanding common stock are fully paid and nonassessable and any additional shares of common stock that we issue will be fully paid and nonassessable.

Anti-Takeover Effects of Certain Charter and Bylaw Provisions and Delaware Law

        Our Certificate of Incorporation and Bylaws and Delaware law contain provisions that could make the following transactions more difficult: acquisition of us by means of a tender offer; acquisition of us by means of a proxy contest or otherwise; or removal of our incumbent officers and directors. It is possible that these provisions could make it more difficult to accomplish or could deter transactions that stockholders may otherwise consider to be in their best interest or in our best interests, including transactions that might result in a premium over the market price for our shares.

        The provisions of our Certificate of Incorporation and Bylaws and Delaware law summarized below may have the effect of deterring hostile takeovers or delaying changes in control or management of us. They are designed to encourage persons seeking to acquire control of us to first negotiate with our Board of Directors. We believe that the benefits of increased protection of our potential ability to negotiate with the proponent of an unfriendly or unsolicited proposal to acquire or restructure us outweigh the disadvantages of discouraging these proposals because negotiation of these proposals could result in an improvement of their terms.

Charter and Bylaw Provisions

        Our Certificate of Incorporation and Bylaws contain provisions relating to corporate governance and to the rights of stockholders. Our Bylaws provide that special meetings of stockholders may only be called by our Board of Directors, our Chairman of the Board or our Chief Executive Officer and shall be called by our Chairman, Chief Executive Officer or Secretary at the request in writing of stockholders owning at least one-fourth of the outstanding shares of capital stock entitled to vote. In addition, our Certificate of Incorporation provides that our Board of Directors may authorize the issuance of preferred stock without further stockholder approval and upon those terms and conditions, and having those rights, privileges and preferences, as our Board of Directors may determine.

        Since the terms of our Certificate of Incorporation and Bylaws may differ from the general information we are providing, you should only rely on the actual provisions of our Certificate of Incorporation and Bylaws. If you would like to read our Certificate of Incorporation and Bylaws, they are available as described under the heading "Where You Can Find More Information."

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Delaware Anti-Takeover Law

        We are subject to the provisions of Section 203 of the Delaware General Corporation Law. ("DGCL"). In general, this section prohibits a publicly held Delaware corporation from engaging in a business combination with an interested stockholder for a period of three years after the date of the transaction in which the person becomes an interested stockholder, unless:

        Section 203 defines "business combination" to include:

        An interested stockholder is a person who, together with affiliates and associates, owns, or at any time within the prior three years did own, 15% or more of the corporation's voting stock. Business combinations include, without limitation, mergers, consolidations, stock sales, asset sales or other transactions resulting in a financial benefit to interested stockholders.

Other Rights and Restrictions

        Holders of our common stock do not have preemptive or subscription rights, and they have no right to convert their common stock into any other securities. There are no redemption or sinking fund provisions applicable to the common stock. The rights, preferences and privileges of common stockholders are subject to the rights of the stockholders of any series of preferred stock which we may designate in the future. Our Certificate of Incorporation and Bylaws do not restrict the ability of a holder of common stock to transfer the holder's shares of common stock.

Listing

        Our common stock is listed on the NASDAQ Capital Market under the symbol "CDTI."

Transfer Agent and Registrar

        The transfer agent and registrar for our common stock is American Stock Transfer & Trust Company, LLC.

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DESCRIPTION OF PREFERRED STOCK

        The following description of our preferred stock, together with the additional information we include in any applicable prospectus supplement, summarizes the material terms and provisions of our preferred stock that we may offer under this prospectus. For the complete terms of our preferred stock, please refer to our Certificate of Incorporation and Bylaws, and the applicable certificate of designation to our Certificate of Incorporation ("Certificate of Designation") establishing the terms of the related series of preferred stock. See "Where You Can Find More Information." The descriptions herein and in the applicable prospectus supplement do not contain all of the information that you may find useful or that may be important to you. You should refer to the provisions of our Certificate of Incorporation, the applicable Certificate of Designation and our Bylaws because they, and not the summaries, define your rights as holders of shares of our preferred stock. The terms of our preferred stock also may be affected by Delaware law.

Authorized and Outstanding Shares

        We currently have authorized 100,000 shares of preferred stock, $0.01 par value per share, none of which have been issued. The Board of Directors has the right, without shareholder approval, to issue preferred stock and to establish its terms and conditions.

Designations, Powers, Preferences, Rights, Qualifications, Limitations and Restrictions

        Prior to issuance of shares of each series of our undesignated preferred stock, our Board of Directors is required by the DGCL and our Certificate of Incorporation to adopt resolutions and file a Certificate of Designations with the Secretary of State of the State of Delaware, fixing for each such series the designations, powers, preferences, rights, qualifications, limitations and restrictions of the shares of such series.

        Our Board of Directors could authorize the issuance of shares of preferred stock with terms and conditions which could have the effect of discouraging a takeover or other transaction which holders of some, or a majority, of such shares might believe to be in their best interests or in which holders of some, or a majority, of such shares might receive a premium for their shares over the then-market price of such shares.

        Subject to limitations prescribed by the DGCL, our Certificate of Incorporation and our Bylaws, our Board of Directors is authorized to fix the number of shares constituting each series of preferred stock and the designations, powers, preferences, rights, qualifications, limitations and restrictions of the shares of such series, including such provisions as may be desired concerning voting, redemption, dividends, dissolution or the distribution of assets, conversion or exchange, and such other subjects or matters as may be fixed by resolution of the Board of Directors. Each series of preferred stock that we offer under this prospectus will, when issued, be fully paid and nonassessable and will not have, or be subject to, any preemptive or similar rights.

        The applicable prospectus supplement will describe the following terms of the series of preferred stock in respect of which this prospectus is being delivered:

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Transfer Agent and Registrar

        The transfer agent and registrar for our preferred stock will be set forth in the applicable prospectus supplement.


DESCRIPTION OF WARRANTS

        The following description, together with the additional information we may include in any applicable prospectus supplement, summarizes the material terms and provisions of the warrants that we may offer under this prospectus and any related warrants, warrant agreements and warrant certificates. While the terms summarized below will apply generally to any warrants that we may offer, we will describe the particular terms of any series of warrants in more detail in the applicable prospectus supplement. If we indicate in the prospectus supplement, the terms of any warrants offered under that prospectus supplement may differ from the terms described below.

        We will file as exhibits to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of warrant, warrant certificate and/or warrant agreement agreement that describes the terms of the series of warrants we are offering, and any supplemental agreements, before the issuance of the related series of warrants. The following summaries of material terms and provisions of the warrants are subject to, and qualified in their entirety by reference to, all the provisions of the warrant, warrant certificate and/or warrant agreement applicable to the particular series of warrants that we may offer under this prospectus. We urge you to read the applicable prospectus supplements related to the particular series of warrants that we may offer under this prospectus and the complete warrants, warrant certificates and/or warrant agreements that contain the terms of the warrants. For more information, please review the forms of these documents, which will be filed with the SEC and will be available as described under the heading "Where You Can Find More Information."

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        The following is a summary of our outstanding warrants:

 
  Shares   Weighted Average
Exercise Price
  Range of
Exercise Prices

Outstanding and exercisable at December 31, 2014 and May 11, 2015

    1,610,069   $ 3.54   $1.25 - $10.40

Aggregate intrinsic value at May 11, 2015

  $ 193,010          

General

        We may issue warrants for the purchase of common stock or preferred stock in one or more series. We may issue warrants independently or together with common stock or preferred stock, and the warrants may be attached to or separate from these securities.

        We will evidence each series of warrants by warrants or warrant certificates that we will issue under a separate agreement. We may enter into a warrant agreement with a warrant agent. If we elect to do so, the warrant agent will act solely as our agent in connection with the warrants and will not assume any obligation or relationship of agency or trust for or with any registered holders of warrants or beneficial owners of warrants. We will indicate the name and address and other information regarding the warrant agent in the applicable prospectus supplement relating to a particular series of warrants if we elect to use a warrant agent.

        We will describe in the applicable prospectus supplement the terms of the series of warrants, including:

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        Before exercising their warrants, holders of warrants will not have any of the rights of holders of the securities purchasable upon such exercise, including the right to receive dividends, if any, or, payments upon our liquidation, dissolution or winding up or to exercise voting rights, if any.

Exercise of Warrants

        Each warrant will entitle the holder to purchase the securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to 5:00 p.m., Pacific Standard Time, on the expiration date that we set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void. Holders of warrants may exercise their respective warrants in the manner set forth in the applicable prospectus supplement relating to such warrants. We will set forth in the warrant or on the reverse side of the warrant certificate and in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver to the warrant agent.

        Upon receipt of the required payment and the warrant exercise notice or certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will issue and deliver the securities purchasable upon such exercise. If fewer than all of the warrants represented by the warrant or warrant certificate are exercised, then we may issue a new warrant or warrant certificate for the remaining amount of warrants as specified therein. If we so indicate in the applicable prospectus supplement, holders of the warrants may surrender securities as all or part of the exercise price for warrants.

Enforceability of Rights by Holders of Warrants

        Each warrant agent will act solely as our agent under the applicable warrant agreement and will not assume any obligation or relationship of agency or trust with any holder of any warrant. A single bank or trust company may act as warrant agent for more than one issue of warrants. A warrant agent will have no duty or responsibility in case of any default by us under the applicable warrant agreement or warrant, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a warrant may, without the consent of the related warrant agent or the holder of any other warrant, enforce by appropriate legal action its right to exercise, and receive the securities purchasable upon exercise of, its warrants.

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DESCRIPTION OF UNITS

        The following description, together with the additional information we may include in any applicable prospectus supplements, summarizes the material terms and provisions of the units that we may offer under this prospectus and any related unit agreements and unit certificates. While the terms summarized below will apply generally to any units that we may offer, we will describe the particular terms of any series of units in more detail in the applicable prospectus supplement. If we indicate in the prospectus supplement, the terms of any units offered under that prospectus supplement may differ from the terms described below.

        We will file as exhibits to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, any form of unit agreement that describes the terms of the series of units we are offering, and any supplemental agreements, before the issuance of the related series of units. The following summaries of material terms and provisions of the units are subject to, and qualified in their entirety by reference to, all the provisions of such unit agreements and any supplemental agreements applicable to a particular series of units. We urge you to read the applicable prospectus supplements related to the particular series of units that we may offer under this prospectus and the complete unit agreement and any supplemental agreements that contain the terms of the units. For more information, please review the forms of these documents, which will be filed with the SEC and will be available as described under the heading "Where You Can Find More Information."

General

        We may issue, in one or more series, units comprised of shares of our common stock or preferred stock and warrants to purchase common stock or preferred stock or any combination. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date.

        We may evidence units by unit certificates that we issue under a separate agreement. We may issue the units under a unit agreement between us and one or more unit agents. If we elect to enter into a unit agreement with a unit agent, the unit agent will act solely as our agent in connection with the units and will not assume any obligation or relationship of agency or trust for or with any registered holders of units or beneficial owners of units. We will indicate the name and address and other information regarding the unit agent in the applicable prospectus supplement relating to a particular series of units if we elect to use a unit agent.

        We will describe in the applicable prospectus supplement the terms of the series of units being offered, including:

        The other provisions regarding our common stock, preferred stock and warrants as described in this section will apply to each unit to the extent such unit consists of shares of our common stock and preferred stock and warrants to purchase our common stock.

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Enforceability of Rights by Holders of Units

        Each unit agent will act solely as our agent under the applicable unit agreement and will not assume any obligation or relationship of agency or trust with any holder of any unit. A single bank or trust company may act as unit agent for more than one series of units. A unit agent will have no duty or responsibility in case of any default by us under the applicable unit agreement or unit, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a unit may, without the consent of the related unit agent or the holder of any other unit, enforce by appropriate legal action its rights as holder under any security included in the unit.


PLAN OF DISTRIBUTION

        We may sell the securities offered by this prospectus in one or more of the following ways from time to time:

        In addition, we may issue the securities being offered by this prospectus as a dividend or distribution.

        We may effect the distribution of the securities from time to time in one or more transactions at a fixed price or prices, which may be changed from time to time, at market prices prevailing at the time of sale, at prices related to prevailing market prices or at negotiated prices.

        We will set forth in a prospectus supplement the terms of the offering of our securities, including:

Sale through Underwriters

        If we use an underwriter or underwriters in the sale of securities offered by this prospectus, the underwriters will acquire the securities for their own account, including through underwriting, purchase, security lending or repurchase agreements with us. The underwriters may resell the securities from time to time in one or more transactions, including negotiated transactions. Underwriters may sell the

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securities in order to facilitate transactions in any of our other securities (described in this prospectus or otherwise), including other public or private transactions and short sales.

        Underwriters may offer securities to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more firms acting as underwriters. Unless otherwise indicated in the prospectus supplement, the obligations of the underwriters to purchase the securities will be subject to certain conditions, and the underwriters will be obligated to purchase all the offered securities if they purchase any of them. The underwriters may change from time to time any public offering price and any discounts or concessions allowed or re-allowed or paid to dealers.

        If we use an underwriter or underwriters in the sale of securities, we will execute an underwriting agreement with the underwriter or underwriters at the time we reach an agreement for sale. We will set forth in the applicable prospectus supplement the names of the specific managing underwriter or underwriters, as well as any other underwriters, and the terms of the transactions, including compensation of the underwriters and dealers. This compensation may be in the form of discounts, concessions or commissions.

        We may grant to the underwriters options to purchase additional securities to cover over-allotments, if any, at the public offering price with additional underwriting discounts or commissions. If we grant any over-allotment option, the terms of any over-allotment option will be set forth in the prospectus supplement relating to those securities.

Sale Through Dealers

        If we use dealers in the sale of the securities offered by this prospectus, we or an underwriter will sell the securities to them as principals. The dealers may then resell those securities to the public at varying prices to be determined by the dealers at the time of resale. The applicable prospectus supplement will set forth the names of the dealers and the terms of the transactions.

Direct Sales

        We may directly solicit offers to purchase the securities offered by this prospectus. In this case, no underwriters or agents would be involved. We may sell the securities directly to institutional investors or others who may be deemed to be underwriters within the meaning of the Securities Act with respect to any sale of those securities. The terms of any such sales will be described in the prospectus supplement.

Sale Through Agents

        Securities also may be offered and sold through agents designated from time to time. The prospectus supplement will name any agent involved in the offer or sale of the securities and will describe any commissions payable to the agent. Unless otherwise indicated in the applicable prospectus supplement, any agent will agree to use its reasonable best efforts to solicit purchases for the period of its appointment. Any agent may be deemed to be an underwriter within the meaning of the Securities Act with respect to any sale of those securities.

Delayed Delivery Contracts

        If the applicable prospectus supplement indicates, we may authorize agents, underwriters or dealers to solicit offers from institutions to purchase securities at the public offering price under delayed delivery contracts. These contracts would provide for payment and delivery on a specified date in the future. Institutions with which contracts of this type may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions, but in all cases those institutions must be approved by us. The obligations of any purchaser

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under any contract of this type will be subject to the condition that the purchase of the securities shall not at the time of delivery be prohibited under the laws of the jurisdiction to which the purchaser is subject. The applicable prospectus supplement will describe the commission payable for solicitation of those contracts.

Market Making, Stabilization and Other Transactions

        Our common stock is listed on the NASDAQ Capital Market. Any common stock sold pursuant to a prospectus supplement will be eligible for listing and trading on the NASDAQ Capital Market, subject to official notice of issuance. Unless the applicable prospectus supplement states otherwise, each other class or series of securities issued will be a new issue and will have no established trading market. We may elect to list any other class or series of securities on an exchange, but we are not currently obligated to do so.

        Any underwriters that we use in the sale of offered securities may make a market in such securities, but may discontinue such market making at any time without notice. Therefore, we cannot assure you that the securities will have a liquid trading market. Any underwriter may also engage in stabilizing transactions, syndicate covering transactions and penalty bids in accordance with Regulation M under the Securities Exchange Act of 1934, as amended. Stabilizing transactions involve bids to purchase the underlying security in the open market for the purpose of pegging, fixing or maintaining the price of the securities. Syndicate covering transactions involve purchases of the securities in the open market after the distribution has been completed in order to cover syndicate short positions.

        Penalty bids permit the underwriters to reclaim a selling concession from a syndicate member when the securities originally sold by the syndicate member are purchased in a syndicate covering transaction to cover syndicate short positions. Stabilizing transactions, syndicate covering transactions and penalty bids may cause the price of the securities to be higher than it would be in the absence of the transactions. The underwriters may, if they commence these transactions, discontinue them at any time.

        The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. Such transactions, if commenced, may be discontinued at any time. We make no representation or prediction as to the direction or magnitude of any effect that the transactions described above, if implemented, may have on the price of our securities.

Derivative Transactions and Hedging

        We, the underwriters or other agents may engage in derivative transactions involving the securities. These derivatives may consist of short sale transactions and other hedging activities. The underwriters or agents may acquire a long or short position in the securities, hold or resell securities acquired and purchase options or futures on the securities and other derivative instruments with returns linked to or related to changes in the price of the securities. In order to facilitate these derivative transactions, we may enter into security lending or repurchase agreements with the underwriters or agents. The underwriters or agents may effect the derivative transactions through sales of the securities to the public, including short sales, or by lending the securities in order to facilitate short sale transactions by others.

        The underwriters or agents may also use the securities purchased or borrowed from us or others (or, in the case of derivatives, securities received from us in settlement of those derivatives) to directly or indirectly settle sales of the securities or close out any related open borrowings of the securities.

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Electronic Auctions

        We also may make sales through the Internet or through other electronic means. Since we may from time to time elect to offer securities directly to the public, with or without the involvement of agents, underwriters or dealers, utilizing the Internet or other forms of electronic bidding or ordering systems for the pricing and allocation of such securities, you will want to pay particular attention to the description of that system we will provide in a prospectus supplement.

        Such electronic system may allow bidders to directly participate, through electronic access to an auction site, by submitting conditional offers to buy that are subject to acceptance by us, and which may directly affect the price or other terms and conditions at which such securities are sold. These bidding or ordering systems may present to each bidder, on a so-called "real-time" basis, relevant information to assist in making a bid, such as the clearing spread at which the offering would be sold, based on the bids submitted, and whether a bidder's individual bids would be accepted, prorated or rejected. Of course, many pricing methods can and may also be used.

        Upon completion of such an electronic auction process, securities will be allocated based on prices bid, terms of bid or other factors. The final offering price at which securities would be sold and the allocation of securities among bidders would be based in whole or in part on the results of the Internet or other electronic bidding process or auction.

General Information

        Agents, underwriters, and dealers may be entitled, under agreements entered into with us, to indemnification by us against specified liabilities, including liabilities under the Securities Act of 1933, or to contribution by us to payments they may be required to make in respect to such liabilities. The applicable prospectus supplement will describe the terms and conditions of indemnification or contribution. Some of our agents, underwriters, and dealers, or their affiliates, may be customers of, engage in transactions with or perform services for us, in the ordinary course of business. We will describe in the prospectus supplement the nature of any such relationship and the name of the parties involved. Any lockup arrangements will be set forth in the applicable prospectus supplement.

        Under Rule 15c6-1 of the Exchange Act, trades in the secondary market generally are required to settle in three business days, unless the parties to any such trade expressly agree otherwise. The applicable prospectus supplement may provide that the original issue date for your securities may be more than three scheduled business days after the trade date for your securities. Accordingly, in such a case, if you wish to trade securities on any date prior to the third business day before the original issue date for your securities, you will be required, by virtue of the fact that your securities initially are expected to settle in more than three scheduled business days after the trade date for your securities, to make alternative settlement arrangements to prevent a failed settlement.

        The securities may be new issues of securities and may have no established trading market. The securities may or may not be listed on a national securities exchange. We can make no assurance as to the liquidity of or the existence of trading markets for any of the securities.


LEGAL MATTERS

        Unless the applicable prospectus supplement indicates otherwise, certain legal matters with respect to the validity of the securities offered under this prospectus and any prospectus supplement will be passed upon for us by DLA Piper LLP (US), Phoenix, Arizona. Counsel for any underwriter or agent will be noted in the applicable prospectus supplement.

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EXPERTS

        The consolidated financial statements of Clean Diesel Technologies, Inc. as of December 31, 2014 and 2013 and for each of the two years in the period ended December 31, 2014, incorporated by reference in this prospectus and in the registration statement have been so incorporated in reliance on the report of BDO USA, LLP, independent registered public accounting firm (the report on the consolidated financial statements contains an explanatory paragraph regarding the Company's ability to continue as a going concern), incorporated herein by reference, given on the authority of said firm as experts in auditing and accounting.


WHERE YOU CAN FIND MORE INFORMATION

        We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy any document we file at the SEC's Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. You can request copies of these documents by writing to the SEC and paying a fee for the copying cost. Please call the SEC at 1-800-SEC-0330 for more information about the operation of the public reference room. Our SEC filings are also available to the public at the SEC's web site at http://www.sec.gov.

        We have filed with the SEC a registration statement on Form S-3 under the Securities Act relating to the securities covered by this prospectus. The registration statement, including the attached exhibits and schedules, contains additional relevant information about us and the securities. This prospectus does not include all of the information contained in the registration statement. Whenever a reference is made in this prospectus to a contract or other document, the reference is only a summary and you should refer to the exhibits that form a part of the registration statement for a copy of the contract or other document. You can get a copy of the registration statement, at prescribed rates, from the sources listed above. You can also obtain these documents from us, without charge (other than exhibits, unless the exhibits are specifically incorporated by reference), by requesting them in writing or by telephone at the following address:

Investor Relations Manager
Clean Diesel Technologies, Inc.
1621 Fiske Place
Oxnard, CA 93033
(805) 639-9555
Internet Website: www.cdti.com


INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

        The SEC allows us to "incorporate by reference" into this prospectus the information contained in the documents we file with the SEC, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus, and later information that we file with the SEC will update and supersede this information.

        This prospectus incorporates by reference the documents listed below that we have previously filed with the SEC. These documents contain important information about us:

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        All filings that we may file pursuant to the Exchange Act subsequent to the date hereof and prior to effectiveness of this registration statement shall be deemed to be incorporated in this registration statement and to be a part hereof from the date of filing of such documents or reports. In addition, we incorporate by reference any additional documents that we may file with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act (other than those furnished pursuant to Item 2.02 or Item 7.01 of Form 8-K or other information "furnished" to the SEC), from the date of the registration statement of which this prospectus is part until the termination of the offering of the securities. These documents may include annual, quarterly and current reports, as well as proxy statements. Any material that we later file with the SEC will automatically update and replace the information previously filed with the SEC. These documents are available to you without charge. See "Where You Can Find More Information."

        For purposes of this prospectus, any statement contained in a document incorporated or deemed to be incorporated herein by reference shall be deemed to be modified or superseded to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated herein by reference modifies or supersedes such statement in such document.

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CLEAN DIESEL TECHNOLOGIES INCORPORATED

$50,000,000

Common Stock
Preferred Stock
Warrants
Units



PROSPECTUS

                    , 2015

   


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PART II
INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14.    Other Expenses Of Issuance And Distribution.

        The following table sets forth the fees and expenses, other than underwriting discounts and commissions, payable by the Company in connection with the issuance and distribution of the offered securities. All of the amounts shown are estimates except the SEC registration fee.

SEC registration fee

  $ 2,228  

Legal fees and expenses

      *

Accounting fees and expenses

      *

Printing fees and expenses

      *

Other fees and expenses

      *

Total

  $   *

*
These fees cannot be estimated at this time, as they are calculated based on the securities offered and the number of issuances. An estimate of the aggregate expenses in connection with the sale and distribution of the securities being offered will be included in the applicable prospectus supplement.

Item 15.    Indemnification of Directors and Officers

        Subsection (a) of Section 145 of the Delaware General Corporation Law empowers a corporation to indemnify any person who was or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of the corporation) by reason of the fact that he or she is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses (including attorneys' fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by him or her in connection with such action, suit or proceeding if he or she acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe his or her conduct was unlawful.

        Subsection (b) of Section 145 empowers a corporation to indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the corporation to procure a judgment in its favor by reason of the fact that he or she is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses (including attorneys' fees) actually and reasonably incurred by him or her in connection with the defense or settlement of such action or suit if he or she acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the corporation and except that no indemnification shall be made in respect of any claim, issue or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the Court of Chancery or the court in which such action or suit was brought shall determine upon application that, despite the adjudication of liability but in view of all of the circumstances of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Court of Chancery or such other court shall deem proper.

        Section 145 further provides that to the extent a director or officer of a corporation has been successful in the defense of any action, suit or proceeding referred to in subsection (a) and (b) or in the defense of any claim, issue or matter therein, he or she shall be indemnified against expenses

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(including attorneys' fees) actually and reasonably incurred by him or her in connection therewith; that the indemnification provided by Section 145 shall not be deemed exclusive of any other rights to which the indemnified party may be entitled; and that the scope of indemnification extends to directors, officers, employees, or agents of a constituent corporation absorbed in a consolidation or merger and persons serving in that capacity at the request of the constituent corporation for another. Section 145 also empowers a corporation to purchase and maintain insurance on behalf of a director or officer of the corporation against any liability asserted against him or her or incurred by him or her in any such capacity or arising out of his or her status as such whether or not the corporation would have the power to indemnify him or her against such liabilities under Section 145.

        Article VIII of Clean Diesel Technologies, Inc.'s Restated Certificate of Incorporation, as amended ("Certificate of Incorporation"), specifies that CDTI shall indemnify its directors, officers, employees and agents to the full extent that such right of indemnity is permitted by law. This provision is deemed to be a contract between CDTI and each director and officer who serves in such capacity at any time while such provision and the relevant provisions of the Delaware General Corporation Law are in effect, and any repeal or modification thereof shall not offset any right to indemnification in respect of action, suit or proceeding theretofore or thereafter brought or threatened based in whole or in part upon any such state of facts. The amendment or repeal of such provision of the Certificate of Incorporation may be effected by the affirmative vote of the holders of a majority in interest of all outstanding capital stock of Clean Diesel entitled to vote, in person or by proxy, at any annual or special meeting in which a quorum is present.

        Section 102(b)(7) of the Delaware General Corporation Law enables a corporation in its certificate of incorporation to limit the personal liability of members of its Board of Directors for violation of a director's fiduciary duty of care. This section does not, however, limit the liability of a director for breaching his or her duty of loyalty, failing to act in good faith, engaging in intentional misconduct or knowingly violating a law, authorizing unlawful payments of dividends or unlawful redemptions or stock purchases as contemplated by Section 174 of Delaware General Corporation Law, or from any transaction in which the director derived an improper personal benefit. This section also will have no effect on claims arising under the federal securities laws.

        Clean Diesel's Certificate of Incorporation limits the liability of its directors as authorized by Section 102(b)(7). To amend such provisions the Company would require the affirmative vote of the holders of a majority of the voting power of all outstanding shares of the capital stock of CDTI.

        CDTI has obtained liability insurance for the benefit of its directors and officers which provides coverage for losses of directors and officers for liabilities arising out of claims against such persons acting as directors or officers of Clean Diesel (or any subsidiary thereof) due to any breach of duty, neglect, error, misstatement, misleading statement, omission or act done by such directors and officers, except as prohibited by law.

Item 16.    Exhibits

        See the Exhibit Index attached to this registration statement that is incorporated herein by reference.

Item 17.    Undertakings

(1)
The undersigned registrant hereby undertakes:

(1)
To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i)
To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

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SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Oxnard, State of California, on the 19th day of May 2015.

    CLEAN DIESEL TECHNOLOGIES, INC.

 

 

By:

 

/s/ CHRISTOPHER J. HARRIS

Christopher J. Harris
President and Chief Executive Officer
(principal executive officer)

 

 

By:

 

/s/ DAVID E. SHEA

David E. Shea
Chief Financial Officer (principal financial and accounting officer)


POWER OF ATTORNEY

        The undersigned hereby constitutes and appoints Christopher J. Harris, David E. Shea and Pedro J. Lopez-Baldrich and each of them, as his true and lawful attorneys-in-fact and agents, jointly and severally, with full power of substitution and re-substitution, for and in his stead, in any and all capacities, to sign on his behalf this Registration Statement on Form S-3 in connection with the registration of securities by the registrant and offering thereof pursuant hereto and to execute any amendments thereto (including post-effective amendments), including a registration statement filed pursuant to Rule 462(b), or certificates that may be required in connection with this Registration Statement, and to file the same, with all exhibits thereto, and all other documents in connection therewith, with the Securities and Exchange Commission and granting unto said attorneys-in-fact and agents, and each of them, jointly and severally, the full power and authority to do and perform each and every act and thing necessary or advisable to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or any of them, jointly or severally, or their or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities below.

Signature
 
Title
 
Date

 

 

 

 

 
/s/ CHRISTOPHER J. HARRIS

Christopher J. Harris
  President and Chief Executive Officer (principal executive officer)   May 19, 2015

/s/ DAVID E. SHEA

David E. Shea

 

Chief Financial Officer, (principal financial and accounting officer)

 

May 19, 2015

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Signature
 
Title
 
Date

 

 

 

 

 
/s/ CHARLES R. ENGLES, PH.D.

Charles R. Engles, Ph.D.
  Chairman   May 19, 2015

/s/ MATTHEW BEALE

Matthew Beale

 

Director

 

May 19, 2015

/s/ DR. TILL BECKER

Dr. Till Becker

 

Director

 

May 19, 2015

/s/ LON E. BELL, PH.D.

Lon E. Bell, Ph.D.

 

Director

 

May 19, 2015

/s/ BERNARD H. ("BUD") CHERRY

Bernard H. ("Bud") Cherry

 

Director

 

May 19, 2015

/s/ MUNGO PARK

Mungo Park

 

Director

 

May 19, 2015

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INDEX TO EXHIBITS

Exhibit Number   Description
  1.1 * Form of Underwriting Agreement

 

2.1

 

Asset Purchase Agreement, dated as of October 20, 2014, between Clean Diesel Technologies, Inc., ECS Holdings, Inc., Engine Control Systems Ltd., and SES USA Inc. (incorporated by reference to Exhibit 2.1 to CDTi's Current Report on Form 8-K (SEC file number 001-33710) filed on October 21, 2014).

 

3.1

 

Restated Certificate of Incorporation of Clean Diesel Technologies, Inc., as amended through May 23, 2012. (incorporated by reference to Exhibit 3.1 to CDTi's Annual Report on Form 10-K (SEC file number 001-33710) filed on March 18, 2015).

 

3.2

 

By-Laws of Clean Diesel Technologies, Inc. as amended through November 6, 2008 (incorporated by reference to Exhibit 3.1 to CDTi's Quarterly Report on Form 10-Q (SEC file number 001-33710) filed on November 10, 2008).

 

4.1

 

Specimen of Certificate for Clean Diesel Common Stock (incorporated by reference to Exhibit 4.1 to Clean Diesel's Post-Effective Amendment No. 1 to Form S-4 on Form S-3 (file number 333-166865) filed on November 10, 2010).

 

4.2

*

Form of Certificate of Designations for Preferred Stock

 

4.3

*

Form of Warrant Agreement

 

4.4

*

Form of Warrant

 

4.5

*

Form of Unit Agreement

 

5.1

 

Opinion of DLA Piper LLP (US)

 

23.1

 

Consent of BDO USA, LLP, Independent Registered Public Accounting Firm

 

23.2

 

Consent of DLA Piper LLP (US) (included in Exhibit 5.1)

 

24.1

 

Power of Attorney (included on signature page hereto)

*
To be filed by amendment or as an exhibit to a report pursuant to Section 13(a), 13(c) or 15(d) of the Exchange Act.

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