UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the Fiscal Year Ended December 31, 2018 Commission file number 1-5153 Marathon Oil® Marathon Oil Corporation (Exact name of registrant as specified in its charter) Delaware 25-0996816 (State or other jurisdiction of incorporation or organization) (I.R.S. Employer Identification No.) 5555 San Felipe Street, Houston, TX 77056-2723 (Address o ...