In 1984, Standard Oil of California was renamed to Chevron Corporation; and it bought Gulf Oil—the largest merger in history at that time.[54] To meet anti-trust regulations, Chevron divested many of Gulf's operating subsidiaries, and sold some Gulf stations and a refinery in the eastern United States to British Petroleum and Cumberland Farms in 1985.[55] In 1987, British Petroleum negotiated the acquisition of Britoil[56] and the remaining publicly traded shares of Standard Oil of Ohio.[5] At the same year it was listed on the Tokyo Stock Exchange where its share were traded until delisting in 2008.[57]