Marathon Completes Sale of Its Interests in Heimdal Area Offshore Norway

Marathon Oil Corporation announced the completion of the sale of its non-operated interests in the Heimdal infrastructure, related producing fields and associated undeveloped acreage offshore Norway. Centrica plc, the parent company of British Gas, acquired the interests for a total value of $416 million, which includes a $375 million purchase price and $41 million in associated Norwegian asset tax pools, with an effective date of Jan. 1, 2008.

The sale of these non-core Norwegian assets is part of Marathon’s ongoing review of its global asset portfolio and the Company’s goal to achieve $2 – $4 billion in gross proceeds by mid-year 2009.

Under the terms of the sale, Centrica acquired Marathon’s 23.8 percent interest in the Heimdal field, as well as its 46.9 percent interest in the Vale field; a 20 percent interest in the Byggve field; a 20 percent interest in the Skirne field; and a 50 and 20 percent interest in the Peik and Heimdal East discoveries, respectively. Marathon’s net proved reserves associated with these assets as of year end 2007 were 4.8 million barrels of oil equivalent (mmboe), and total net risked resources of approximately 17.5 mmboe. Current net production from these operations averaged approximately 7,000 barrels of oil equivalent per day during the first three quarters of 2008. None of the assets involved in this agreement are associated with Marathon’s Alvheim/Vilje development or related operations on the Norwegian Continental Shelf.

Marathon is an integrated international energy company engaged in exploration and production; oil sands mining; integrated gas; and refining, marketing and transportation operations. Marathon, which is based in Houston, has principal operations in the United States, Angola, Canada, Equatorial Guinea, Gabon, Indonesia, Ireland, Libya, Norway and the United Kingdom. Marathon is the fourth largest United States-based integrated oil company and the nation’s fifth largest refiner.