8-K

UNITED STATES

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): June 12, 2013

Marathon Oil Corporation

 __________________________________________

 (Exact name of registrant as specified in its charter)

Delaware	1-5153		25-0996816
_____________________  (State or other jurisdiction	_____________  (Commission		______________  (I.R.S. Employer
of incorporation)	File Number)		Identification No.)
5555 San Felipe Street, Houston, Texas			77056
_________________________________  (Address of principal executive offices)			___________  (Zip Code)
Registrant's telephone number, including area code:		(713) 629-6600

Not Applicable

 ______________________________________________

 Former name or former address, if changed since last report

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

[  ]	Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
[  ]	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
[  ]	Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
[  ]	Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

On June 13, 2013, Marathon Oil Corporation (the “Company”) announced that Clarence P. Cazalot, Jr., chairman, president and CEO of the Company, has elected to retire effective December 31, 2013 after almost 14 years leading the Company. Effective August 1, 2013, Mr. Cazalot will serve as Executive Chairman through December 31, 2013. The Company has no employment agreement with Mr. Cazalot, and he will not receive any severance payments upon his retirement. The treatment of his compensation upon retirement will be consistent with the Company's past practice and programs as described on pages 54-55 and 65-68 of the Company's 2013 Proxy Statement.

On June 13, 2013, the Company also announced that the Board of Directors (the “Board”) elected Lee M. Tillman to the Board and to succeed Mr. Cazalot as president and CEO effective August 1, 2013. Since 2010, Mr. Tillman, 51, served as vice president of Engineering for ExxonMobil Development Company where he was responsible for all global engineering staff engaged in major project concept selection, front end design and engineering. Between 2007 and 2010, he served as North Sea production manager and lead country manager in Stavanger, Norway. From 2006 to 2007, he served as acting vice president, ExxonMobil Upstream Research Company. Mr. Tillman began his career in the oil and gas industry at Exxon Mobil Corporation in 1989 as a research engineer and has extensive operations management and leadership experience that has included assignments in Jakarta, Indonesia; Aberdeen, Scotland; Stavanger, Norway; Malabo, Equatorial Guinea; Dallas and New Orleans. He holds a bachelor of science degree in chemical engineering with honors from Texas A&M University and a PhD in chemical engineering from Auburn University. Mr. Tillman has extensive knowledge and experience in global operations, project execution and leading edge technology. At this time, no determination has been made with respect to related person transactions for Mr. Tillman.

As president and CEO, Mr. Tillman will receive a base salary of $1,000,000 per year. Mr. Tillman will participate in the Company's annual cash bonus program with a target award of 125% of base salary. In addition, Mr. Tillman will receive a cash sign-on bonus of $3,000,000, less required tax withholdings and subject to certain repayment obligations, to be paid in three installments. The first installment of $2,000,000 will be payable within 30 days of August 1, 2013, the second installment of $500,000 will be payable within 30 days of August 1, 2014, and the third installment of $500,000 will be payable within 30 days of August 1, 2015. Mr. Tillman will also receive a sign-on grant of Company restricted stock valued at $1,000,000. One-third of the restricted shares granted will vest on the first anniversary of the date of grant, one-third of the shares granted will vest on the second anniversary of the date of grant, and one-third of the shares granted will vest on the third anniversary of the date of grant. He will also receive grants of stock options and restricted stock representing the 2013 annual long-term incentive awards. As soon as administratively feasible, Mr. Tillman will receive a grant of restricted shares valued at approximately $3,000,000, which will cliff vest on the third anniversary of the date of grant, and a grant of stock options valued at approximately $3,000,000 with one-third of the options vesting on the first anniversary of the date of grant, one-third of the options vesting on the second anniversary of the date of grant, and one-third of the options vesting on the third anniversary of the date of grant. Beginning in February 2014, Mr. Tillman will become eligible to participate in the Company's annual long-term incentive awards program. Mr. Tillman will participate in all other elements of the Company's executive compensation and benefits plans, including as an eligible participant in the Company's retirement plans. Those plans are outlined in the Company's 2013 Proxy Statement. Like Mr. Cazalot, Mr. Tillman will not have an employment agreement with the Company.

Mr. Tillman will not receive any fees for his service on the Board.

Item 5.03. Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year.

On June 12, 2013, the Board amended the Company's By-laws (“By-laws”). The amendments are effective August 1, 2013. Article III, Section 3.1 was amended to provide that the Chairman may be an officer of the Company. Section 3.2 was added to provide that the Chairman of the Board may be an employee or officer of the Company and will preside at meetings of the Board and stockholders. Former Sections 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, and 3.9 were renumbered to 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, and 3.10, respectively, and Article VI, Section 6.10(a) was amended to provide that a Lead Director will be elected by the Board if the Chairman is not independent. The By-laws did not provide for a Chairman position, and these amendments were necessary to allow Mr. Cazalot to serve as Executive Chairman and to otherwise ensure the Company would have an independent Lead Director during such time as Mr. Cazalot served as Executive Chairman.

As amended, Article III, Section 3.1 of the By-laws provides, in part, that the principal officers of the Company will be elected by the Board and that all other offices, titles, powers and duties with respect to principal officers shall be determined by the Board from time to time, which can include the Chairman as an officer of the Company. Article III, Section 3.2 of the By-laws provides, in part, that the Chairman of the Board may be an employee or officer of the Company and will, if present, preside at meetings of the Board and stockholders, exercise and perform such other duties as may be assigned by the Board and report to the Board. Article VI, Section 6.10(a) of the By-laws provides, in part, that the definition of “Lead Director” shall mean the Director elected by the Board, not less than annually, by the affirmative vote of a majority of the non-employee Directors in the event (i) the

Chairman and Chief Executive Officer positions are not separate, or (ii) the Chairman is not independent according to the standards for director independence set forth in the Company's Corporate Governance Principles.

The foregoing summary of the amendments to the By-laws is qualified in its entirety by reference to the complete amendments to Sections 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9 and 6.10(a) of the By-laws, which are attached hereto as Exhibit 3.1 and incorporated herein by reference.

9.01. Financial Statements and Exhibits

3.1Amendments to By-laws of Marathon Oil Corporation

SIGNATURE

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

Date:  June 17, 2013		MARATHON OIL CORPORATION
	By:	/s/ Sylvia J. Kerrigan
		Sylvia J. Kerrigan
		Executive Vice President, General Counsel & Secretary

Exhibit Index

3.1    Amendments to By-laws of Marathon Oil Corporation

EX-3.1

Exhibit 3.1

Amendments to By-laws of Marathon Oil Corporation

Effective August 1, 2013, Article III, Sections 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, and 3.10 of the Company's By-laws will be amended to read in full:

Section 3.1. Officers. The principal officers of the Corporation will be elected by the Board and shall include a chief executive officer, president, chief accounting officer, chief financial officer, vice presidents, general counsel, secretary and treasurer. All other offices, titles, powers and duties with respect to principal officers shall be determined by the Board from time to time, which can include the Chairman as an officer of the Corporation. Each principal officer who shall be a member of the Board of Directors shall be considered an officer-director.

The Board of Directors or any Board Committee or officer designated by it may appoint such other officers as necessary, who shall have such authority and shall perform such duties as from time to time may be assigned to them by or with the authority of the Board of Directors.

One person may hold two or more offices.

In its discretion, the Board of Directors may leave unfilled any office.

All officers, agents and employees shall be subject to removal at any time by the Board of Directors. All officers, agents and employees, other than officers elected by the Board of Directors, shall hold office at the discretion of the committee or of the officer appointing them.

Each of the salaried officers of the Corporation shall devote his entire time, skill and energy to the business of the Corporation, unless the contrary is expressly consented to by the Board of Directors.

Section 3.2. Chairman of the Board. The Chairman of the Board may be an employee or officer of the Corporation and will, if present, preside at meetings of the Board of Directors and stockholders. The Chairman of the Board will exercise and perform such other duties as may be assigned by the Board of Directors. The Chairman of the Board will report to the Board of Directors.

Section 3.3. Powers and Duties of the Chief Executive Officer. Subject to the Board of Directors, the chief executive officer of the Corporation shall be in general charge of the affairs of the Corporation.

Section 3.4. Powers and Duties of the President. Subject to the chief executive officer and the Board of Directors, the president shall have such duties as may be assigned by the Board.

Section 3.5. Powers and Duties of the Chief Accounting Officer and Chief Financial Officer. The chief accounting officer and chief financial officer shall each have such authority and shall perform such duties, as may be assigned by the Board.

Section 3.6. Powers and Duties of the General Counsel. The general counsel shall be the chief consulting officer of the Corporation in all legal matters, and, subject to the Board of Directors, shall have general control of all matters of legal import concerning the Corporation.

Section 3.7. Powers and Duties of the Treasurer. Subject to the officer designated by the Board of Directors, the treasurer shall have custody of all the funds and securities of the Corporation which may have come into the hand of the Corporation; when necessary or proper he or she shall endorse, or cause to be endorsed, on behalf of the Corporation, for collection, checks, notes and other obligations, and shall cause the deposit of same to the credit of the Corporation in such bank or banks or depositary as the Board of Directors may designate or as the Board of Directors by resolution may authorize; he or she shall sign all receipts and vouchers for payments made to the Corporation other than routine receipts and vouchers, the signing of which he or she may delegate; he or she shall sign all checks made by the Corporation; provided, however, that the Board of Directors may authorize and prescribe by resolution the manner in which checks drawn on banks or depositaries shall be signed, including the use of facsimile signatures, and the manner in which officers, agents or employees shall be authorized to sign; he or she may sign with the president or a vice president all certificates of shares in the capital stock; whenever required by the Board of Directors, he or she shall render a statement of his or her cash account; he or she shall enter regularly, in books of the Corporation to be kept for the purpose, full and accurate account of all moneys received and paid by him or her on account of the Corporation; he or she shall, at all reasonable times, exhibit his or her books and accounts to any director of the Corporation upon application at his or her office during business hours; and he or she shall perform all acts incident to the position of treasurer.

The treasurer shall give a bond for the faithful discharge of the assigned duties in such sum as the Board of Directors may require.

Section 3.8. Powers and Duties of Secretary. The secretary shall keep the minutes of all meetings of the Board of Directors, and the minutes of all meetings of the stockholders, and also (unless otherwise directed by the Board of Directors) the minutes of all committees, in books provided for that purpose; he or she shall attend to the giving and serving of all notices of the Corporation; he or she may sign with any other duly authorized person, in the name of the Corporation, all contracts authorized by the Board of Directors, and affix the seal of the Corporation thereto; he or she shall have charge of the certificate books, transfer books and stock ledgers, and such other books and papers as the Board of Directors may direct, all of which shall, at all reasonable times, be open to the examination of any director, upon application at the secretary's office during business hours; and he or she shall in general perform all the duties incident to the office of secretary, subject to the control of the Board of Directors.

Section 3.9. Voting upon Interests in Other Business Entities. Unless otherwise ordered by the Board of Directors, any person or persons appointed in writing by any of them shall have full power and authority on behalf of the Corporation to attend and to act and to vote at any meetings of stockholders of any corporation in which the Corporation may hold stock, or at any other meetings of holders of ownership interests in business entities in which the Corporation may hold an interest, including limited liability companies, and at any such meeting shall possess and may exercise any and all rights and powers incident to the ownership of such stock or other interest, and which, as the owner thereof, the Corporation might have possessed and exercised if present. The Board of Directors, by resolution, from time to time, may confer like powers upon any other person or persons.

Section 3.10. Term of Office, etc. Each officer will hold office until the first regular meeting of the Board in each year (at which a quorum shall be present) held next after the annual meeting of stockholders, and until a successor is elected and qualified or until such officer's earlier resignation or removal. No officer of the Corporation will have any contractual right against the Corporation for compensation by reason of the election or appointment as an officer of the Corporation beyond the date of service as such, except as a written employment or other contract otherwise may provide. The Board may remove any officer with or without cause at any time, but any such removal will not prejudice the contractual rights of that officer, if any, against the Corporation. The Board by resolution may fill any vacancy occurring in any office of the Corporation by death, resignation, removal or otherwise for the unexpired portion of the term of that office at any time.

Effective August 1, 2013, Article VI, Section 6.10 of the Company's By-laws will be amended to read in full:

Section 6.10 Certain Definitional Provisions. (a) In these By-laws:

“Board” or “Board of Directors” means the board of directors of the Corporation.

“Board Committee” means any committee of the Board.

“Certificate of Incorporation” means at any time the original certificate of incorporation of the Corporation as amended and restated from time to time to that time, including each certificate of designation, if any, respecting any class or series of preferred stock of the Corporation.

“Chairman” or “chairman” means the chairman of the Board.

“DGCL” means the General Corporation Law of the State of Delaware.

“Exchange Act” means the Securities Exchange Act of 1934, as amended.

“Lead Director” means the Director elected by the Board, not less than annually, by the affirmative vote of a majority of the non-employee Directors in the event (i) the Chairman and Chief Executive Officer positions are not separate, or (ii) the Chairman is not independent according to the categorical standards for director independence set forth in the Corporation's Corporate Governance Principles.

“Secretary” or “secretary” means the secretary of the Corporation.

(b)When used in these By-laws, the words “herein,” “hereof” and “hereunder” and words of similar import refer to these By-laws as a whole and not to any provision of these By-laws, and the words “Article” and “Section” refer to Articles and Sections of these By-laws unless otherwise specified.

(c)Whenever the context so requires, the singular number includes the plural and vice versa, and a reference to one gender includes the other gender and the neuter.

(d)The word “including” (and, with correlative meaning, the word “include”) means including, without limiting the generality of any description preceding that word, and the words “shall” and “will” are used interchangeably and have the same meaning.