Marathon Oil (MRO)

5.900% Notes due 2018

A series of Securities are hereby established pursuant to Section 3.01 of the Indenture dated as of February 26, 2002 between Marathon Oil Corporation (the “Company”) and The Bank of New York Trust Company, N.A., successor in interest to JPMorgan Chase Bank (the “Trustee”), relating to senior debt securities of the Company (the “Indenture”) as follows:

1. Each capitalized term used but not defined herein shall have the meaning assigned to such term in the Indenture.

2. The title of such series of Securities shall be the “5.900% Senior Notes due 2018” (the “Notes”). The Notes will be offered pursuant to the Indenture. The price at which the Notes shall be issued is 99.792%.

3. The aggregate principal amount of the Notes that may be initially authenticated and delivered under the Indenture shall be $1,000,000,000 (except for Notes authenticated and delivered upon registration of transfer of, or in exchange for, or in lieu of, other Notes pursuant to Section 3.04, 3.05, 3.06, 9.06 or 11.07 of the Indenture, and except for any Notes which, pursuant to Section 3.03 of the Indenture, shall be deemed never to have been authenticated and delivered thereunder).

4. The date on which the principal of the Notes is due and payable, unless accelerated pursuant to the Indenture, is March 15, 2018.

5. The Notes shall bear interest at the rate of 5.900% per annum. The date from which interest shall accrue for the Notes shall be March 17, 2008. Interest shall be payable semiannually on March 15 and September 15 of each year (each, an “Interest Payment Date”), commencing September 15, 2008, to each Person in whose name the Notes (or one or more Predecessor Securities) are registered at the close of business on the Regular Record Date for such interest. The Regular Record Dates for interest payable on the Notes shall be the March 1 or September 1 (as the case may be), whether or not a Business Day, immediately preceding an Interest Payment Date. Interest on the Notes shall be calculated on the basis of a 360-day year consisting of twelve 30-day months.

6. The Notes shall be issuable only in denominations of $1,000 and any integral multiple thereof. Subject to any prior conditions stated in the Indenture, the Notes shall be issued in definitive form.

7. The place or places where (a) the principal of, premium (if any) and interest on the Notes shall be payable, (b) the Notes may be surrendered for registration of transfer or for exchange and (c) notices may be given to the Company in respect of the Notes, is the Corporate Trust Office of the Trustee in New York, New York, or such other offices or agencies maintained for such purposes as the Company may designate from time to time and in accordance with the Indenture; provided that payment of interest, other than at Maturity, may be made, at the option of the Company, by check mailed to the address of the Person entitled thereto as such address shall appear in the Security Register or by electronic funds transfer to an account maintained by the Person entitled thereto as such account shall appear in the Security Register.

8. The Notes are subject to redemption upon not less than 30 days’ notice by mail, at any time, in whole or in part, at the election of the Company, at a Redemption Price equal to the greater of (1) 100% of the principal amount of such Notes to be redeemed or (2) the sum of the present values of the remaining scheduled payments of principal and interest on the Notes to be redeemed (exclusive of interest accrued to the date of redemption) discounted to the date of redemption on a semiannual basis (assuming a 360-day year consisting of twelve 30-day months) at the then current Treasury Rate plus 40 basis points, plus, in either case, accrued and unpaid interest on the principal amount being redeemed to the date of redemption. For purposes of the foregoing:

“Business Day” means any calendar day that is not a Saturday, Sunday or legal holiday in New York, New York or Houston, Texas and on which commercial banks are open for business in New York, New York and Houston, Texas.

“Comparable Treasury Issue” means the United States Treasury security selected by an Independent Investment Banker as having a maturity comparable to the remaining term (“Remaining Life”) of the Securities to be redeemed that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of such Securities.

“Comparable Treasury Price” means, with respect to any redemption date, (1) the average of the Reference Treasury Dealer Quotations for such redemption date, after excluding the highest and lowest Reference Treasury Dealer Quotations, or (2) if the Trustee obtains fewer than four such Reference Treasury Dealer Quotations, the average of all such quotations.

“Independent Investment Banker” means one of the Reference Treasury Dealers that the Company appoints to act as the Independent Investment Banker from time to time.

“Reference Treasury Dealer” means each of Citigroup Global Markets Inc., Morgan Stanley & Co. Incorporated, Banc of America Securities LLC and J.P. Morgan Securities Inc. (each a “Primary Treasury Dealer”) and their respective successors which the Company may specify from time to time; provided, however, that if any of them ceases to be a Primary Treasury Dealer, the Company shall substitute therefor another Primary Treasury Dealer.

“Reference Treasury Dealer Quotations” means, with respect to each Reference Treasury Dealer and any redemption date, the average, as determined by the Trustee, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Trustee by such Reference Treasury Dealer at 5:00 p.m., New York City time, on the third Business Day preceding such redemption date.

“Treasury Rate” means, with respect to any redemption date, the rate per annum equal to: (1) the yield, under the heading which represents the average for the immediately preceding week, appearing in the most recently published statistical release designated “H.15(519)” or any successor publication which is published weekly by the Board of Governors of the Federal Reserve System and which establishes yields on actively traded United States Treasury securities adjusted to constant maturity under the caption “Treasury Constant Maturities,” for the maturity corresponding to the Comparable Treasury Issue; provided that, if no maturity is within three months before or after the Remaining Life of the Securities to be redeemed, yields for the two published maturities most closely corresponding to the Comparable Treasury Issue shall be determined and the Treasury Rate shall be interpolated or extrapolated from such yields on a straight line basis, rounding to the nearest month; or (2) if such release (or any successor release) is not published during the week preceding the calculation date or does not contain such yields, the rate per annum equal to the semiannual equivalent yield to maturity of the Comparable Treasury Issue, calculated using a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for such redemption date. The Treasury Rate shall be calculated on the third Business Day preceding the redemption date.

Notice of the redemption will be mailed to each Holder of the applicable series of Notes to be redeemed by first-class mail at least 30 and not more than 60 days prior to the date fixed for redemption. If fewer than all of the Notes are to be redeemed, the Trustee will select, not more than 60 days prior to the Redemption Date, the particular Notes or portions thereof for redemption from the Outstanding Notes not previously called by such method as the Trustee deems fair and appropriate.

9. The Notes are not subject to any sinking fund or analogous provisions. The Notes will not be redeemable at the option of the Holder thereof prior to Maturity.

10. The Company will not pay additional amounts on any of the Notes to Holders in respect of any tax, assessment or governmental charge withheld or deducted.

11. The Notes may be purchased only in currency of the United States and payment of principal of, premium, (if any), and interest on the Notes will only be made in currency of the United States.

12. The Events of Default and covenants specified in the Indenture will apply to the Notes without additions or changes.

13. One hundred percent (100%) of the principal amount of the Notes will be payable upon declaration of acceleration of the Maturity thereof pursuant to Section 5.02 of the Indenture.

14. The defeasance and covenant defeasance provisions of Article XIII of the Indenture will apply to the Notes.

15. The Notes shall be issued in the form of one or more Global Securities (the “Global Notes”). The Depository for the Global Notes shall be The Depository Trust Company, a New York corporation (“DTC”), and the Global Notes shall be registered in the name of DTC or Cede & Co., as a nominee of DTC. Except as set forth in Sections 2.03 or 3.05 of the Indenture, such Global Notes may only be transferred, in whole and not in part, to the Depository or another nominee of the Depository.

16. The Trustee will initially act as the Security Registrar for the Notes and as the Paying Agent with respect to the Notes.

17. The Notes and the Trustee’s certificate of authentication shall be substantially in the form of Exhibit 1 hereto.

Exhibit 1