Did the Rally End for U.S. Refinery Stocks That Lost 4 Trillion Won in a Day?

Shares of Marathon Petroleum Corp. (MPC) plunged 5.06% to close at $233 on the New York Stock Exchange on the 8th. Its market capitalization fell to about $68.6 billion (roughly 93 trillion won), erasing some $3.3 billion (around 4.5 trillion won) in a single day.

In early February, the company reported its fourth-quarter and full-year 2025 results, citing strong refining margins and robust cash generation, and confirmed it would continue its shareholder-return policy. That same month, Marathon signed a multi-year agreement with Baker Hughes to supply refining-process chemicals and digital monitoring technology to U.S. refineries.

The refining sector has been one of the quiet winners in U.S. markets through mid-March, and Marathon Petroleum’s stock had risen by about 30% this year, suggesting that the recent pullback may reflect heightened volatility after a steep rally.

Headquartered in Findlay, Ohio, Marathon Petroleum is the largest refining system operator in the United States, with integrated downstream and midstream operations capable of processing about 3 million barrels per day. Through its Marathon and ARCO branded retail networks and logistics infrastructure, the company supplies transportation fuels such as gasoline and diesel, along with petrochemical products. Its subsidiary MPLX also manages midstream assets, including pipelines and storage facilities.