X0202 4 2005-01-03 0 0000101778 MARATHON OIL CORP MRO 0001237640 LADER PHILIP C/O MARATHON OIL CORPORATION 5555 SAN FELIPE ROAD HOUSTON TX 77056 1 0 0 0 COMMON STOCK 2005-01-03 4 A 0 811.249 36.98 A 7851.778 D COMMON STOCK 2005-01-03 4 A 0 1622.499 36.98 A 9474.277 D Deferral of one-half of $60,000 annual retainer in common stock units. Common stock units vest upon reporting person's departure from the Board of Directors. Shares of common stock will be issued upon vesting of common stock units. Annual non-retainer common stock units granted under Marathon Oil Corporation 2003 Incentive Compensation Plan. Common stock units vest upon reporting person's departure from the Board of Directors. Shares of common stock will be issued upon vesting of common stock units. Includes dividends of 183.588 shares previously not reported pursuant to Rule 16a-11. By: R. J. Kolencik, Attorney-in-Fact for Philip Lader 2005-01-05