Marathon Petroleum Corporation (MPC) Stock Analysis & Winston Score

Marathon Petroleum Corporation turns crude oil into everyday products like gasoline, diesel, and jet fuel. It sells these fuels to gas stations, trucking companies, airlines, and other businesses across the United States. Marathon is one of the largest oil refiners in the country and also owns the Speedway-branded fuel network through its MPLX pipeline and logistics business. Marathon makes money by buying crude oil, refining it, and selling the finished products at a higher price — the difference is called the refining margin. It operates primarily in the United States, with refineries spread across the Midwest, Gulf Coast, and West Coast, giving it broad geographic reach. The company's large refining capacity and extensive pipeline network through its MPLX partnership create real scale advantages over smaller competitors. The main risk is that refining margins are cyclical and can shrink quickly when crude oil prices rise faster than fuel prices, which directly squeezes profits.