British Petroleum acquired 25% of Standard Oil of Ohio in August 1969, a majority in 1978 and full ownership in June 1987, forming BP America. The 60/40 Amoco merger took effect on 1 January 1999 as BP Amoco. Atlantic Richfield merged into it on 18 April 2000, and the name became BP plc in 2001.
Keep the explicit scope label independent; no alias or company identity is inferred.