Marathon Petroleum is a petroleum and energy refining, processing, and marketing company. Until 2011, it was a fully owned subsidiary of Marathon Oil. MPC operates the largest petroleum refining system in the U.S. as of 2025. The marketing arm includes Marathon-branded retail outlets—gas stations offering Marathon gasoline, plus car washing services and convenience store items. In addition to its refining and fuel businesses, the company makes ingredients for household items such as carpeting and PVC pipes. Through a partnership with MPLX, Marathon Petroleum provides fuel logistics and distribution services.
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