Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  Guidry Steven P
2. Date of Event Requiring Statement (Month/Day/Year)
07/01/2011
3. Issuer Name and Ticker or Trading Symbol
MARATHON OIL CORP [MRO]
(Last)
(First)
(Middle)
C/O MARATHON OIL CORPORATION, 5555 SAN FELIPE RD.
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
V.P. - Business Development
5. If Amendment, Date Original Filed(Month/Day/Year)
07/06/2011
(Street)

HOUSTON, TX 77056
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Employee Stock Option (Right to Buy) 05/25/2012(1) 05/25/2021 Common Stock 33,867 $ 33.06 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Guidry Steven P
C/O MARATHON OIL CORPORATION
5555 SAN FELIPE RD.
HOUSTON, TX 77056
      V.P. - Business Development  

Signatures

Yvonne R. Kunetka, Attorney-in-Fact for Steven P. Guidry 07/08/2011
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Vests in three cumulative annual installments of 11,289, 11,289 and 11,289 on May 25, 2012, 2013, and 2014, respectively.
 
Remarks:
This amended Form 3 is being filed to correct the number of Employee Stock Options that expire on May 25, 2021 from 33,705 shares to 33,867 shares, and also to correct the number of shares for the incremental vesting from three cumulative annual installments of 11,235 shares each on May 25, 2012, 2013 and 2014, respectively, to three cumulative annual installments of 11,289  shares each on May 25, 2012, 2013 and 2014, respectively.

All other shares, Stock Appreciation Rights and Employee Stock Options reported on the original Form 3 filing are correct.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, See Instruction 6 for procedure.

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