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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549


                                    FORM 8-K

                                 CURRENT REPORT


     PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934


        DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED): AUGUST 12, 2003



                              PLAINS RESOURCES INC.
               (EXACT NAME OF REGISTRANT AS SPECIFIED IN CHARTER)



       DELAWARE                                         13-2898764
(STATE OF INCORPORATION)                   (I.R.S. EMPLOYER IDENTIFICATION NO.)

                                     0-9808
                              (COMMISSION FILE NO.)


                          500 DALLAS STREET, SUITE 700
                              HOUSTON, TEXAS 77002
                    (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)
                                   (ZIP CODE)


       REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE: (713) 739-6700


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ITEM 7.       FINANCIAL STATEMENTS AND EXHIBITS

              (c) Exhibit 99.1 - Press Release dated August 12, 2003

ITEM 9 AND 12. REGULATION FD DISCLOSURE; RESULTS OF OPERATIONS AND FINANCIAL
CONDITION

         Plains Resources Inc. (the "Company", "our", "we" or "us") today issued
a press release reporting its second quarter results. The Company is furnishing
the press release, attached as Exhibit 99.1, pursuant to Item 9 and Item 12 of
Form 8-K. The Company is also furnishing pursuant to Item 9 its estimates of
certain operating and financial results for the three months ended September 30,
2003 and the year ended December 31, 2003. In accordance with General
Instruction B.2. of Form 8-K, the information presented under this Item 9,
including Exhibit 99.1, shall not be deemed "filed" for purposes of Section 18
of the Securities Act of 1934, as amended, nor shall it be deemed incorporated
by reference in any filing under the Securities Act of 1933, as amended, except
as expressly set forth by specific reference in such a filing.

FORWARD-LOOKING STATEMENTS AND ASSOCIATED RISKS

         All statements, other than statements of historical fact, included in
this report are forward-looking statements, including, but not limited to,
statements identified by the words "anticipate," "believe," "estimate,"
"expect," "plan," "intend" "will" and "forecast" and similar expressions and
statements regarding our business strategy, plans and objectives of our
management for future operations. These statements reflect our current views
with respect to future events, based on what we believe are reasonable
assumptions. These statements, however, are subject to certain risks,
uncertainties and assumptions, including, but not limited to:

o    the consequences of any potential change in the relationship between us and
     Plains Exploration & Production Company;

o    the consequences of our and Plains Exploration's officers and employees
     providing services to both us and Plains Exploration and not being required
     to spend any specified percentage of or amount of their time on our
     business;

o    risks, uncertainties and other factors that could have an impact on Plains
     All American Pipeline, L.P., or PAA, which could in turn impact the value
     of our holdings in PAA (for a discussion of these risks, uncertainties and
     other factors, see PAA's filings with the SEC);

o    the effects of our indebtedness, which could adversely restrict our ability
     to operate, could make us vulnerable to general adverse economic and
     industry conditions, could place us at a competitive disadvantage compared
     to our competitors that have less debt, and could have other adverse
     consequences;

o    uncertainties inherent in the exploration for and development and
     production of oil and gas and in estimating reserves;

o    unexpected future capital expenditures (including the amount and nature
     thereof);

o    impact of oil and gas price fluctuations, particularly given the
     termination of hedge accounting for our hedges;

o    the effects of competition;

o    the success of our risk management activities;

o    the availability (or lack thereof) of acquisition or combination
     opportunities;

o    the impact of current and future laws and governmental regulations;

o    environmental liabilities that are not covered by an indemnity or
     insurance; and

o    general economic, market or business conditions.


                                       2


         If one or more of these risks or uncertainties materialize, or if
underlying assumptions prove incorrect, actual results may vary materially from
those in the forward-looking statements. Except as required by applicable
securities laws, we do not intend to update these forward-looking statements and
information.

DISCLOSURE OF 2003 ESTIMATES

         The following table and accompanying notes reflect current estimates of
certain results for the three months ended September 30, 2003 and the year ended
December 31, 2003 for the Company. These estimates are based on assumptions and
estimates that management believes are reasonable based on currently available
information; however, management's assumptions and the Company's future
performance are both subject to a wide range of business risks and uncertainties
and there is no assurance that these goals and estimates can or will be met. Any
number of factors could cause actual results to differ materially from those in
the following table, including but not limited to the factors discussed above.
The estimates set forth below are given as of the date hereof only based on
information available as of the date hereof. The Company undertakes no
obligation to publicly update or revise any forward-looking statements. Further
information on risks and uncertainties is available in the Company's filings
with the Securities and Exchange Commission ("SEC"), and we encourage you to
review such filings.


                                       3


                              PLAINS RESOURCES INC.
                        OPERATING AND FINANCIAL GUIDANCE




                                                                         THREE MONTHS ENDED       YEAR ENDED
                                                                         SEPTEMBER 30, 2003    DECEMBER 31, 2003
                                                                         ------------------    -----------------
                                                                                         
ESTIMATED PRODUCTION VOLUMES
Barrels of oil - MBbl                                                             200 - 210            850 - 900
 MBbl per day                                                                     2.2 - 2.3            2.3 - 2.5
% Oil                                                                                   100%                 100%

ESTIMATED OIL PRICE DIFFERENTIAL TO NYMEX (PRE-HEDGE) - $/Bbl               $  7.00 - $8.50     $   7.00 - $8.50

CRUDE OIL HEDGE POSITIONS - BARRELS PER DAY
Swaps - average price $26.10 per barrel                                               1,500                1,500

OPERATING COSTS PER BARREL
Production expenses                                                         $  8.10 - $8.25     $   7.80 - $7.95
Production and ad valorem taxes                                             $  1.25 - $1.35     $   1.25 - $1.35
Oil transportation expenses                                                 $  4.00 - $4.25     $   4.00 - $4.25
DD&A - oil and gas                                                                    $4.68                $4.68


OTHER INCOME (EXPENSE) ($ IN THOUSANDS)
Equity in earnings of Plains All American Pipeline, L.P.                    $ 5,100 -$5,900     $22,100 -$24,000
General and administrative expense
   Cash expense                                                             $    600 - $700     $ 3,000 -$ 3,300
   Noncash compensation expense                                                         750                2,900
                                                                            ---------------     ----------------
   Total general and administrative expense                                 $1,350 - $1,450     $ 5,900 - $6,200
                                                                            ===============     ================

Interest expense                                                                     Note 6               Note 6
Other DD&A                                                                  $           100     $            400
Accretion of asset retirement obligation                                    $            60     $            225

BOOK TAX RATE
Current                                                                                  18%                  18%
Deferred                                                                                 30%                  30%

WEIGHTED AVERAGE EQUIVALENT SHARES OUTSTANDING (IN THOUSANDS)
Basic                                                                                23,372               23,552
Restricted stock                                                                        311                  311
Options (treasury method assuming $14.15 common stock price)                            312                  246
Series D Preferred (if dilutive)                                                         --                  710
                                                                            ---------------     ----------------
Diluted shares                                                                       23,995               24,819
                                                                            ===============     ================

CAPITAL EXPENDITURES ($ IN THOUSANDS)                                       $1,000 - $1,500     $ 3,500 - $4,000

DISTRIBUTIONS FROM PLAINS ALL AMERICAN PIPELINE, L.P. ($ IN THOUSANDS)
General partner interest                                                    $           815     $          3,128
Limited partner units                                                                 6,976               27,752
                                                                            ---------------     ----------------
                                                                            $         7,791     $         30,880
                                                                            ---------------     ----------------



                                       4


Notes:

1.       Estimated production volumes. Production estimates are based on
         historical operating performance and trends and the Company's 2003
         capital budget and assume that market demand and prices for oil and gas
         will continue at levels that allow for profitable production of these
         products. SEC Staff Accounting Bulletin 101 ("SAB 101") requires that
         revenue from oil production be recognized as the volumes are sold
         versus when produced. The location of the Company's Florida properties
         and the timing of the barges that transport the oil to market cause
         reported sales volumes to differ from production volumes. Actual timing
         of sales volumes is difficult to predict. The Company's oil production
         is typically sold in shipments of approximately 110,000-140,000 barrels
         and typically occurs every 30-50 days.

2.       Estimated oil price differentials. The Company's realized wellhead oil
         price is lower than the NYMEX index level as a result of area and
         quality differentials. Differentials like commodity prices are
         difficult to predict and increased significantly over recent levels
         during the first half of 2003.

3.       Discontinuation of hedge accounting. During the first quarter of 2003,
         the NYMEX oil price and the price the Company receives for its Florida
         oil production did not correlate closely enough for the Company's
         hedges to qualify for hedge accounting pursuant to the provisions of
         SFAS No. 133 "Accounting for Derivative Instruments and Hedging
         Activities". As a result, the Company was required to discontinue hedge
         accounting effective February 1, 2003 and reflect the mark-to-market
         value of its hedges in earnings. Previously, the Company included gains
         or losses for hedges in earnings based on cash settlements for the
         period that the related volumes were delivered. The foregoing financial
         guidance does not include assumptions or projections with respect to
         potential gains or losses related to changes in fair value recognized
         pursuant to SFAS 133, as there is no accurate way to forecast these
         potential gains or losses. Absent a stable oil price environment, the
         potential gains or losses related to SFAS 133 are likely to materially
         change reported net income and increase the volatility of reported net
         income due to non-cash mark-to-market gains or losses.

4.       General and administrative expense. Estimated G&A expense for the third
         quarter and year ended December 31, 2003 includes approximately $0.8
         million and $2.9 million, respectively of noncash compensation expense,
         primarily related to restricted stock grants to officers and directors
         of the Company. Restricted shares are included in the weighted average
         share count for diluted earnings per share from the date of issuance.
         Restricted shares are included in the share count for basic earnings
         per share when they vest.

5.       Equity in earnings of Plains All American Pipeline, L.P. ("PAA"). The
         Company's equity in earnings from PAA is based on guidance provided by
         PAA in its Form 8-K filed with the SEC on July 29, 2003 and the
         Company's aggregate ownership interest, as adjusted for general partner
         incentive distributions. As of the date hereof, the Company has an
         aggregate ownership interest of approximately 24%, consisting of (i) a
         44% ownership stake in the general partner interest and incentive
         distribution rights, (ii) 45%, or approximately 4.5 million, of the
         subordinated units and (iii) 19%, or approximately 7.9 million of the
         common units (including 1.3 million Class B common units). PAA's Form
         8-K provides guidance of $19.9 million to $23.2 million for its third
         quarter 2003 net income and $88.2 million to $95.8 million for the full
         year 2003. The Company encourages you to refer to the 8-K's filed by
         PAA for additional information concerning guidance provided by PAA,
         including certain expenses that are not


                                       5


         reflected in the net income guidance provided by PAA. These expenses
         relate to the potential vesting of restricted units in 2003. Certain of
         the restricted units may vest in the same proportion as the conversion
         of PAA's subordinated units and others vest when PAA achieves targeted
         distribution levels. PAA will recognize an expense when the financial
         tests for conversion of subordinated units and required distribution
         levels are met. The income effect on the Company's equity in earnings
         of PAA may be somewhat mitigated because the Company may recognize a
         noncash gain when PAA's subordinated units vest. Such gain would be
         similar to the gains that the Company has recognized in the past when
         PAA issues common equity and would be recognized because the
         subordinated units owned by the Company would no longer be subordinated
         in any way to common units, including the right to receive
         distributions, including distributions upon an assumed liquidation of
         PAA.

6.       Interest expense. The Company's interest expense will consist of
         interest on amounts outstanding under its $60 million secured term loan
         facility. Borrowings under the facility bear interest, at the Company's
         option, at LIBOR plus 3% or prime plus 1.5%. The balance outstanding on
         the term loan was $60 million at June 30, 2003. Based on the loan
         amortization schedule, the balance will be reduced to $50.0 million at
         December 31, 2003.

7.       Book tax rate. The Company's book tax rate is based on a Federal rate
         of 35% and an estimated combined foreign and state rate of 13%. The
         foreign tax is attributable to the Canadian operations of PAA and
         represents approximately 80% of the 18% estimated current rate. The
         Company's deferred and current tax rates are based on current estimates
         of book and taxable income and utilization of net operating loss
         carryforwards. At December 31, 2002, the Company had carryforwards of
         approximately $46.4 million of regular tax net operating losses, $15.0
         million of alternative minimum tax net operating losses and
         approximately $3.8 million of enhanced oil recovery credits.

8.       Weighted average equivalent shares outstanding. Estimated basic shares
         are based on shares outstanding on July 31, 2003, net of treasury
         shares and assumes no additional treasury purchases. The Company may
         repurchase additional treasury shares in 2003. Diluted shares include
         the effect of restricted stock and outstanding stock options The
         Company currently has approximately 4.0 million outstanding stock
         options with an average exercise price of $13.39 per share. Utilizing
         the treasury stock method and an assumed stock price of $14.15, the
         closing price on June 30, 2003, the options would add approximately
         312,000 shares and 246,000 shares to the diluted share count for the
         third quarter and year, respectively. If dilutive, the Series D
         Preferred shares will be included in the diluted share count for the
         period prior to June 4, 2003, the date the Series D was repurchased by
         the Company.

9.       Capital expenditures. Capital expenditures are based on the Company's
         2003 capital budget for its oil and gas properties. These expenditures
         do not include any estimated amounts for capital contributions that the
         Company may be required to make for its general partner interest in
         PAA. When PAA issues equity, the general partner is required to
         contribute cash to maintain its 2% general partner interest. In March
         2003, PAA issued 2.6 million shares in a public equity offering. The
         Company was required to make a cash capital contribution to the general
         partner of PAA in the amount of $0.6 million for its 44% interest in
         the general partner. If PAA issues equity in the future, the company
         will be required to make additional cash capital contributions.

10.      Distributions from Plains All American Pipeline, L.P. The estimated
         cash distributions for the third quarter are based on PAA's $0.55 per
         unit quarterly distribution ($2.20 on an annual basis)


                                       6


         that was declared in August 2003. The estimated cash distributions for
         the twelve months ended December 31, 2003 are based on the actual
         distributions paid by PAA in the first and second quarters plus
         estimated distributions in the third and fourth quarters of $0.55 per
         unit. The amounts presented reflect estimated cash to be received from
         PAA and have not been adjusted for cash taxes.

11.      Write-downs under full cost ceiling test rules. Under the SEC's full
         cost accounting rules, the Company reviews the carrying value of its
         proved oil and gas properties at the end of each quarter. Under these
         rules, capitalized costs of proved oil and gas properties (net of
         accumulated DD&A, and including deferred income taxes) may not exceed a
         "ceiling" equal to the present value (discounted at 10%) of estimated
         future cash flows from proved oil and gas reserves of such properties
         (including the effect of any hedging related activities) reduced by
         future operating expenses, development expenditures and abandonment
         costs (net of salvage values) and estimated future income taxes. The
         rules require that the Company price its future oil and gas production
         at the prices in effect at the end of each fiscal quarter and require a
         write-down if its capitalized costs exceed the "ceiling" even if prices
         decline for only a short period of time. The Company estimates that
         based on the book value of its proved oil and gas properties (including
         related deferred income taxes) and its estimated proved reserves as of
         June 30, 2003, that the Company would have a write-down under the full
         cost ceiling test rules at a net realized price for the Company's oil
         production of approximately $16.00 per barrel. Based on an estimated
         oil differential including oil transportation totaling $11.00 - $12.75
         per barrel, the Company would have a write-down at a NYMEX crude oil
         index price of $27.00 - $28.75 per barrel.


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                                   SIGNATURES


         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Company has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.


                                                    PLAINS RESOURCES INC.



Date:         August 12, 2003                        /s/ Stephen A. Thorington
                                                    ---------------------------
                                                    Stephen A. Thorington
                                                    Executive Vice President
                                                    and Chief Financial Officer


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                               INDEX TO EXHIBITS




EXHIBIT
NUMBER            DESCRIPTION
-------           -----------
               
99.1              Press Release dated August 12, 2003.