The standard oil company was a harmful monopoly
In 1931 Standard Oil Company of New York merged with Vacuum Oil Company (another trust company) to form Socony-Vacuum, which in 1966 became Mobil Oil Corporation. Standard Oil (Indiana) absorbed Standard Oil of Nebraska in 1939 and Standard Oil of Kansas in 1948 and was renamed Amoco Corporation in 1985. OPEC is more of a cartel than a monopoly. First, most of the oil is produced by one country, Saudi Arabia. It has a far greater ability to affect the price by itself by raising or lowering output. Second, all members must agree to the price set by OPEC.