IMPORTANT TAX INFORMATION FOR MARATHON OIL CORPORATION STOCKHOLDERS

Transcription

1 IMPORTANT TAX INFORMATION FOR MARATHON OIL CORPORATION STOCKHOLDERS Marathon Oil Corporation, a Delaware corporation ("Marathon Oil"), distributed (the "Distribution") approximately 356,125,174 shares of common stock of Marathon Petroleum Corporation, a Delaware Corporation ("Marathon Petroleum"), as of 11:59 p.m. Eastern Daylight Savings Time on June 30, 2011 to the holders of record of Marathon Oil common stock (each, a "Marathon Oil" Stockholder). Marathon Oil and Marathon Petroleum are now two unaffiliated, publicly-owned companies. Section 6045B ofthe Internal Revenue Code, as amended (the "Code"), and the underlying Treasury Regulations (the "Regulations") provide that effective January 1,2011 corporations engaging in certain actions that affect the basis of their stock have 45 days after the date of such an action to f Ie with the Internal Revenue Service ("IRS") an information return describing, among other things, the action and the action's quantitative effect on the basis oftheir stock. As an alternative to filing this information return with the IRS, an issuer may post the information return to its public website. The IRS has not yet issued a specific form of information return although one is contemplated by the Internal Revenue Code. The information below is being provided to comply with Code 6045B to the extent possible with respect to the Distribution. Reporting Issuer Marathon Oil Corporation Reg B-1(a)(1)(i) Taxpayer Identification Number # Security Identifiers Marathon Oil Corporation common stock Reg B-1(a)(1)(ii) CUSIP # Ticker Symbol: MRO (New York Stock Exchange) Marathon Petroleum Corporation common stock CUSIP # 56585A 102 Ticker Symbol: MPC (New York Stock Exchange) Contact at reporting issuer Howard J. Thill Reg B-1(a)(1)(iii) Vice President, Investor Relations and Public Affairs Marathon Oil Corporation 5555 San Felipe Road Houston, TX mailto:hjthill@marathonoil.com INFORMATION ABOUT THE DISTRIBUTION In the Distribution, Marathon Oil Stockholders of record received as of 11:59 p.m. Eastern Daylight Savings Time on June 30, 2011 one share of Marathon Petroleum common stock for every two shares of Marathon Oil common stock held. Marathon Oil Stockholders also received cash in lieu of any fractional share of Marathon Petroleum. If you did not receive the Distribution of Marathon Petroleum common stock, this notice does not apply to you. Additionally, this notice does not apply to shares of Marathon Oil common stock sold, exchanged or otherwise disposed of prior to the time of the Distribution.

2 Consult Your Tax Advisor This notice contains our general understanding of the application of certain existing U.S. Federal income tax laws and regulations relating to the Distribution. It is not tax advice and does not purport to become complete or to describe the consequences that may apply to specific Marathon Oil and Marathon Petroleum stockholders. You should consult your own tax advisor regarding the impact of all U.S. Federal state, local and foreign tax law. GENERAL TAX INFORMATION Marathon Oil received a private letter ruling from the Internal Revenue Service that the Distribution of Marathon Petroleum common stock qualifies as a tax-free distribution for U.S. Federal income tax purposes. As a result, U.S. taxpayers generally will not recognize gain or loss for U.S. Federal income tax purposes upon receipt of Marathon Petroleum common shares except to the extent they receive cash in lieu of fractional shares. Outside of the U.S. the Distribution may be considered a taxable event in some countries and you may wish to consult with a tax advisor regarding potential tax issues. TAX BASIS INFORMATION As a consequence of the Distribution, and as noted in the Marathon Petroleum Corporation Form 10, pursuant to Section 358 ofthe Code you will need to allocate the tax basis in your Marathon Oil shares immediately before the Distribution between your Marathon Oil shares and your newly-received Marathon Petroleum shares. If you purchased your Marathon Oil shares for cash, the tax basis for your Marathon Oil shares would generally equal the cost of these shares including commissions or other fees. If you received your Marathon Oil shares as a gift, through an employee compensation arrangement, or through some other means, we recommend that you consult your own tax advisor to determine your tax basis in these shares. If you acquired Marathon Oil shares at different times, you will need to make separate tax basis calculations for each group of shares. The allocation of tax basis between shares of Marathon Oil common stock and Marathon Petroleum common stock you received in the Distribution is based on their relative fair market values at the time of the Distribution. U.S. Federal income tax law does not specify how to determine these fair market values. Fair market value generally is the price at which property would change hands between a willing buyer and a willing seller, neither being under any compulsion to buy or sell and both having reasonable knowledge of the facts. Assumptions Shares of Marathon Oil common stock owned: 100 shares Purchase Price of Marathon Oil Shares: $40 per share Aggregate tax basis for Marathon Oil share: $4,000 (100 shares x $40 share price) Marathon Petroleum Shares received in Distribution 50 shares There are several potential methods for determining the fair market values of Marathon Oil common stock and Marathon Petroleum common stock. One approach for determining the fair market value is to utilize the mean average of the high and low trading prices of Marathon Oil common stock and Marathon Petroleum common stock quoted on the New York Stock Exchange on the trading day after the Distribution, which were $32.68 and $44.215, respectively, on July 1,2011. If you use this method, your aggregate tax basis in Marathon Oil shares immediately prior to the Distribution would be allocated

3 between your Marathon Oil common stock and your newly-received as follows: Marathon Petroleum common shares Tax Basis Allocation Number of Average of NYSE Fair Market Percentage of Allocated Tax Shares Owned High and Low Value 7/1/2011 Total Fair Basis Trading Prices Market Value =(A) x (B) Price 7/1/2011 7/1/2011 Marathon Oil 100 $ $3, % $2, Common Stock (59.65% of $4,000) Marathon 50 $ $2, % $1, Petroleum (40.35% of Common Stock $4,000) Totals $5, % $4,000 Certain Marathon Oil Stockholders (i.e., those stockholders who, immediately before the Distribution, owned 5% or more of Marathon Oil common stock or owned Marathon Oil securities with an aggregate tax basis of$l million or more) who received shares of Marathon Petroleum common stock in the Distribution are required to include a statement related to the Distribution in their U.S. Federal income tax returns for the year in which the Distribution occurs. A sample version ofthis statement is attached to this notice for your convenience, but you should determine, based upon your individual circumstances, whether this notice is appropriate for your use. The information in this document does not constitute tax advice and is not intended or written to be used, and cannot be used, for the purposes of (i) avoid penalties under the Internal Revenue Code or (ii) promoting, marketing or recommending any transaction or matter addressed herein.

4 STATEMENT PURSUANT TO TREASURY REGULATIONS SECTION (b) BY (Name): _ (Taxpayer Identification Number or Social Security Number): _ A SIGNIFICANT DISTRIBUTEE On June 30, 20 II, Marathon Oil Corporation, a Delaware corporation ("Marathon Oil"), distributed (the "Distribution") approximately XXX shares Marathon Petroleum Corporation, a Delaware corporation ("Marathon Petroleum"), of II :59 p.m. Eastern Daylight Savings Time on June 30, 2011 (the "Distribution Date") to the holders of record of Marathon Oil common stock as. As a result of the Distribution, each Marathon Petroleum Stockholder of record as of June 27, 20 II ("the Record Date") was entitled to receive one share of Marathon Petroleum common stock for every two shares of Marathon Oil common stock held by such stockholder as of the Record Date. I. Name, address and employer identification number of the distributing corporation: Marathon Oil Corporation 5555 San Felipe Street Houston, TX EIN: Name, address and employer identification number of the controlled corporation: Marathon Petroleum Corporation 539 South Main Street Findlay, OH EIN: The undersigned was a stockholder owning shares of Marathon Oil Corporation common stock as ofthe Record Date and received shares of Marathon Petroleum common stock in the Distribution. The undersigned received cash in lieu of a fractional share of Marathon Petroleum common stock, which fractional shares were aggregated and sold by the transfer agent. The aggregate fair market value of Marathon Petroleum common stock and cash received by the stockholder was $_ The undersigned did not surrender any stock or securities in Marathon Oil in connection with the Distribution. 5. Marathon Oil received a private letter ruling from the Internal Revenue Service to the effect that the Distribution will qualify as tax-free under Section 355 of the Internal Revenue Code of 1986, as amended. Stockholder's Name (please print) Taxpayer's Signature TaxpayerIdentification Number or Social Security Number IF APPLICABLE, THIS STATEMENT SHOULD BE COMPLETED AND ATTACHED TO YOUR 2011 FEDERAL INCOME TAX RETURN. IT SHOULD NOT BE SENT TO MARATHON OIL OR MARATHON PETROLEUM.

5 Report of Organizational Actions Form 8937 (December 2011) Affecting Basis of Securities OMS No Department of the Treasury Intemal Revenue Service ~ See separate instructions,.:lml. Reporting Issuer 1 Issuer's name 2 Issuer's employer identification number (EIN) Marathon Oil Corporation Name of contact for additional information 4 Telephone No. of contact 5 address of contact Howard J. Thill hjthill@marathonoil.com 6 Number and street (or P.O. box if mall is not delivered to street address) of contact 7 City, town, or post office, state, and Zip code of contact 5555 San Felipe Road Houston TX Date of action 9 Classification and description June Common stock distribution 10 CUSIP number 11 Serial number(s) 12 Ticker symbol 13 Account number(s) 56585A 102 MPC l:lmlll Organizational Action Attach additional statements if needed. See back of form for additional questions. 14 Describe the organizational action and, If applicable, the date 01the action or the date against which shareholders' ownership is measured for the action ~ Marathon Oil Corporation ("MRO") distributed approxitmately ,174 shares of common stock of Marathon Petroleum Corporation ("MPC"). a Delaware corporation. as of 11: 59 p.m. Eastern Daylight Savings Time on June 30, 2011 to the holders of record of MRO common stock. In the distribution, MRO stockholders received one share of MPC common stock for every two shares of MRO stock held. MRO stockholders also received cash in lieu of any fractional share of MPC. As a result of the distribution. MPC became an independent, publicly-traded company. 15 Describe the quantitative effect 01the organizational action on the basis of the security in the hands of a U.S. taxpayer as an adjustment per share or as a percentage of old basis ~ Pursuant to Section 358 of the Internal Revenue Code of 1986, as amended (the "Coden) each MRO stockholder will need to allocate the tax basis in MRO shares immediately before the distribution between shares of MRO common stock and the newly-received shares of MPC common stock. Based upon the average high and low prices on July 1, 2011 (as described below) % of aggregate basis should be allocated to MRO common stock, and 40.35% of aggregate basis should be allocated to MPC common stock. 16 Describe the calculation of the change in basis and the data that supports the calculation, such as the market values of securities and the valuation dates ~ The allocation of tax basis between shares of MRO common stock and MPC common stock is based on their relative fair market values at the time of the distribution. There are several potential methods for determing the fair market values of MRO and MPC common stock.. One approach for determining the fair market value is to utilize the mean averages of the high and low trading prices of MRO and MPC common stock quoted on the New York Stock Exchange on the trading day after the distribution, which were $32.68 and $44.215, respectively, on July If this method is used, the aggregate tax basis in MRO shares would be allocated 59.65% to a taxpayer's shares of MRO common stock and 40.35% to the taxpayer's shares of MPC common stock following the distribution. For Paperwork Reduction Act Notice, see the separate Instructions. Cat. No P Fonn 8937 ( )

6 Form8937 (Rev ) Page 2 Imll. Organizational Action (continued) 17 List the applicable Internal Revenue Code section(s) and subsection(s) upon which the tax treatment is based. The distribution is a tax free reorganization pursuant to Section 368(al(1)JQ) of the Code. The aggregate basis of the MRO common stock and the MPC common stock in the hands of each stockholder is allocated according to fair market value immediately following the spin-off of MPC pursuant to Section 356(b)(2) and 358(c) of the Code. Pursuant to Section 355(a) of the Code, no gain or loss will be recognized by MRO stockholders as a result of the distribution of MPC common stock. Pursuant to section 1223(1) of the Code, the holding period of an MRO stockholder in MPC common stock will include the holding period of the MRO common stock with respect to which the distribution of the MPC common stock was made. 18 Can any resulting loss be recognized?.. No gain or loss will be recognized by MRO stockholders upon their receipt or MPC common stock. 19 Provide any other information necessary to implement the adjustment, such as the reportable tax year. The year of the distribution of MPC common stock was Underpenaltiesof perjury,i declarethat I haveexaminedthis return, includingaccompanyingschedulesand statements,and to the best of my knowledge and belief,it is true, correct,and cornplee. Declarationof preparsr(otherthanouicor)isbasedon all informationof which preparerhasany knowledge. Sign Here Signature~ Date~ i_ >" i t,, /~\:~/ 1/11/ /,1 :' \, J i Print our name~ Stephen J. Landry ntle~ Vice President of Tax PrinVTypepreparer'sname IPreparer'ssignaturo Paid I Dato Check 0 ifjlptin self-employed Preparer Firm'sname Use Only ~ Firm's EIN ~ Firm'saddress ~ Phoneno. Send Form 8937 (including accompanying statements) to: Department of the Treasury, Internal Revenue Service, Ogden, UT