Bygone gas brands include SOHIO (5 letters), AMOCO (5 letters) and ESSO (4 letters). SOHIO was a major American oil company that operated from 1911 to 1986. It was acquired by BP in 1987. AMOCO, which stood for American Oil Company, was an American oil company that operated from 1910 to 1998. It was acquired by BP in 1998. ESSO, which stood for Standard Oil Company, was an American oil company that operated from 1882 to 1972. It was acquired by ExxonMobil in 1972.