Marathon Oil (MRO)

Prohibited Services

The independent auditor shall be prohibited from performing the following services:

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		Marathon Oil Corporation 5555 San Felipe Road Houston, TX 77056

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M MARATHON

Marathon

Oil Corporation

C/O SHAREHOLDER SERVICES P.O. BOX 4813 HOUSTON, TX 77210-4813

VOTE BY INTERNET—www.proxyvote.com

Use the Internet to transmit your voting instructions and for electronic delivery of information up until 11:59 p.m. EDT on April 28, 2009 for shares held by registered holders directly and 11:59 p.m. EDT on April 26, 2009 for shares held in the Marathon Oil Company Thrift Plan. Have your proxy card in hand when you access the web site and follow the instructions to obtain your records and to create an electronic voting instruction form.

VOTE BY PHONE—1-800-690-6903

Use any touch-tone telephone to transmit your voting instructions up until 11:59 p.m. EDT on April 28, 2009 for shares held by registered holders directly and 11:59 p.m. EDT on April 26, 2009 for shares held in the Marathon Oil Company Thrift Plan. Have your proxy card in hand when you call and then follow the instructions.

VOTE BY MAIL

Mark, sign and date your proxy card and return it in the postage-paid envelope we have provided or return it to Marathon Oil Corporation, c/o Broadridge Financial Solutions, Inc., 51 Mercedes Way, Edgewood, NY 11717.

The Internet and telephone voting facilities will close at 11:59 p.m. EDT on April 28, 2009, for shares held by registered holders directly and at 11:59 p.m. EDT on April 26, 2009, for shares held in the Marathon Oil Company Thrift Plan.

TO VOTE, MARK BLOCKS BELOW IN BLUE OR BLACK INK AS FOLLOWS: MACOC1 KEEP THIS PORTION FOR YOUR RECORDS DETACH AND RETURN THIS PORTION ONLY

THIS PROXY CARD IS VALID ONLY WHEN SIGNED AND DATED.

MARATHON OIL CORPORATION

Your Board of Directors recommends you vote “FOR” Items 1 (a) through 1 (m).

1. Election of directors for a one-year term expiring in 2010

For Against Abstain

NOMINEES:

1(a). Charles F. Bolden, Jr. 1(b). Gregory H. Boyce 1(c). Clarence P. Cazalot, Jr. 1(d). David A. Daberko 1(e). William L. Davis 1(f). Shirley Ann Jackson 1(g). Philip Lader 1(h). Charles R. Lee 1(i). Michael E. J. Phelps

Please indicate if you plan to attend this meeting.

Please indicate if you wish to view meeting materials electronically via the Internet rather than receiving a hard copy; please note that you will continue to receive a proxy card for voting purposes only.

For Against Abstain

1(j). Dennis H. Reilley 1(k). Seth E. Schofield 1(l). John W. Snow

1(m). Thomas J. Usher

Your Board of Directors recommends you vote “FOR” Item 2

2. Ratification of the appointment of PricewaterhouseCoopers LLP as our independent auditor for 2009

Your Board of Directors recommends you vote “AGAINST” Item 3

3. Stockholder Proposal to amend our By-laws to lower the threshold for stockholders to call special meetings

Your Board of Directors recommends you vote “AGAINST” Item 4

4. Stockholder Proposal to adopt a policy for ratification of executive compensation

Signature [PLEASE SIGN WITHIN BOX] Date Signature (Joint Owners) Date

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M MARATHON

Marathon

Oil Corporation

2009 ANNUAL MEETING OF STOCKHOLDERS

ATTENDANCE CARD

You are cordially invited to attend the Annual Meeting of Stockholders on Wednesday, April 29, 2009.

The Meeting will be held in the Conference Center Auditorium of the Marathon Oil Tower, 5555 San Felipe Road, Houston, Texas 77056 at 10:00 A.M. Central Time.

(Please detach this card from your proxy card and bring it with you as identification. A map to the meeting site is inscribed on this card for your convenience. The use of an attendance card is for our mutual convenience, however your right to attend without an attendance card, upon proper identification, is not affected.)

William F. Schwind, Jr. Secretary

(FOR THE PERSONAL USE OF THE NAMED STOCKHOLDER(S) ON THE BACK—NOT TRANSFERABLE.)

Important Notice Regarding Internet Availability of Proxy Materials for the Annual Meeting:

The 2009 Notice of Annual Meeting of Stockholders and Proxy Statement and 2008 Annual Report are available at www.proxyvote.com.

A(Proxy must be signed and dated on the reverse side. Please fold and detach card at perforation before mailing.)A

Proxy and Voting Instruction Form

This Proxy and Voting Instruction is solicited on behalf of the Board of Directors for the Annual Meeting of Stockholders on April 29, 2009 For shares held by registered holders

The undersigned hereby appoints Thomas J. Usher, Clarence P. Cazalot, Jr. and Janet F. Clark, or any of them, proxies to vote as herein directed on behalf of the undersigned at the Annual Meeting of Stockholders of Marathon Oil Corporation on Wednesday, April 29, 2009 and at any meeting resulting from any adjournment(s) or postponement(s) thereof and upon all other matters properly coming before the Meeting, including the proposals set forth in the 2009 Notice of Annual Meeting and Proxy Statement for such Meeting with respect to which the proxies are instructed to vote as directed on reverse side. You are encouraged to specify your choice by marking the appropriate boxes on the reverse side, but you need not mark any boxes if you wish to vote in accordance with the Board of Directors’ recommendations. The proxies cannot vote the shares unless you sign and return the proxy card.

For shares held in Marathon Oil Company Thrift Plan

These confidential voting instructions will only be shared with Fidelity Management Trust Company, as Trustee for the Marathon Oil Company Thrift Plan (the “Marathon Plan”). The undersigned, as a participant in the Marathon Plan, hereby directs the Trustee to vote the number of shares of Marathon Oil Corporation common stock credited to the undersigned’s account under the Marathon Plan at the Annual Meeting of Stockholders, and at any meeting resulting from any adjournment(s) or postponement(s) thereof, upon all subjects that may properly come before the meeting, including the matters described in the 2009 Notice of Annual Meeting and Proxy Statement. In the Trustee’s discretion, it may vote upon such other matters as may properly come before the Meeting. Your vote is confidential. The shares credited to the account will be voted as directed on the reverse side. If no direction is made, if the card is not signed, or if the card is not received by April 26, 2009, the shares credited to the account will not be voted. You cannot vote the shares in person at the Annual Meeting; the Trustee is the only one who can vote the shares.

PROXY TO BE SIGNED AND DATED ON THE REVERSE SIDE

Prohibited Services

The independent auditor shall be prohibited from performing the following services:

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		Marathon Oil Corporation 5555 San Felipe Road Houston, TX 77056

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Prohibited Services

The independent auditor shall be prohibited from performing the following services:

·                  Bookkeeping or other services related to the accounting records or financial statements of the audit client;

·                  Financial information systems design and implementation;

·                  Appraisal or valuation services, fairness opinions, or contribution-in-kind reports;

·                  Actuarial services;

·                  Internal audit outsourcing services;

·                  Management functions or human resources;

·                  Broker or dealer, investment adviser, or investment banking services;

·                  Legal services and expert services unrelated to the audit; and

·                  Any other service that the Board determines, by regulation, is impermissible.

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