Defunct companies based in Oklahoma

Conoco ( ), formerly known as Continental Oil, is an American petroleum brand that is operating under the current ownership of the Phillips 66 Company since 2012 and is headquartered in the Westchase neighborhood of Houston, Texas. The brand is one of the several successors of the original Standard Oil Company ("oil trust" founded 1870 by John D. Rockefeller). Conoco was a subsidiary of Standard Oil from 1884 until 1911 when the Supreme Court of the United States, in an anti-trust legal case, ruled to decouple and break up the monopolized entity of Standard Oil.

defunct American oil company, predecessor of ConocoPhillips

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