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Marathon Oil Company was a major American petroleum company of the 20th century with a full range of operations, from exploration and production to refining, marketing, and transportation. Its descendant companies were Marathon Petroleum Corporation, headquartered in Findlay, Ohio, engaged in the refining and distribution of automotive fuel, engine oil, and other petroleum products; and Marathon Oil Corporation, headquartered in Houston, Texas, engaged in the exploration and production of crude oil, natural gas, and oil sands. In 2024 Marathon Oil Corporation was acquired by rival oil company ConocoPhillips.
Marathon Oil, founded in Lima, Ohio, in 1887 as the Ohio Oil Company, came under the control of the Standard Oil Trust in 1889. In 1905 it moved its headquarters to Findlay. When the Standard Oil combine was broken up by the U.S. Supreme Court in 1911, the company again became independent. Formerly only an oil producer, it expanded into refining while it also purchased oil fields beyond Ohio.
In 1930 Ohio Oil bought the Transcontinental Oil Company, which had producing fields in Texas, and it adopted Transcontinentalâs Marathon brand name and trademark long-distance Greek runner for its retail products. Ohio Oil finally adopted the name Marathon Oil Company in 1962. It operated mainly in North America, with some production in Libya and Nigeria and additional refining and wholesaling in Europe.
Marathon became a subsidiary of the United States Steel Corporation in 1982 and in 1986 was reorganized, with U.S. Steel, as part of USX Corporation. In 1990 the company moved its headquarters to Houston. Marathon increased its scope and market share in 1998 by combining some of its operations with Ashland Inc. In 2001 U.S. Steel was separated from USX, and the following year USX was renamed Marathon Oil Corporation.
Marathon embarked on a decade of expansion, acquiring companies such as the Russian Khanty Mansiysk Oil Corporation in 2003 and Canadian Western Oil Sands Inc. in 2007; it also produced oil and gas in the North Sea and the Gulf of Mexico.
In 2011 the company split into two publicly held companies:
In May 2024 rival oil company ConocoPhillips announced a deal to acquire Marathon Oil in a deal valued at $22.5 billion. The acquisition closed in November of that year. Marathon Petroleum continues to operate as an independent company, with shares listed on the New York Stock Exchange under the ticker symbol MPC.
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