Standard Oil an "unreasonable" monopoly under the Sherman Antitrust Act, Section II. It ordered Standard to break up into 34 independent companies with different boards of directors, the biggest two of the companies were Standard Oil of New Jersey (which became Exxon) and Standard Oil of New York (which became Mobil). Standard's president, John D. Rockefeller, had long since retired from any management role. But, as he owned a quarter of the shares of the resultant companies, and those share values mostly doubled, he emerged from the dissolution as the richest man in the world. The dissolution had actually propelled Rockefeller's personal
Standard Oil most of them remained together. The only company since the breakup of Standard Oil that was divided into parts like Standard Oil was AT&T, which after decades as a regulated natural monopoly, was forced to divest itself of the Bell System in 1984. The successor companies from Standard Oil's breakup form the core of today's US oil industry. (Several of these companies were considered among the Seven Sisters who dominated the industry worldwide for much of the 20th century.) They include: Other Standard Oil spin-offs: Other companies divested in the 1911 breakup: Note: Standard Oil of Colorado was not a