Following the 1911 Supreme Court ruling that found Standard Oil was an illegal monopoly, the company was broken up into 34 different entities, divided primarily by region and activity. Many of these companies later became part of the Seven Sisters, which dominated global petroleum production in the 20th century, and became a majority of today's largest investor-owned oil companies, with most tracing their roots back to Standard Oil. Some descendants of Standard Oil were also given exclusive rights to the Standard Oil name.
Today, many of Standard Oil's 34 successor entities play roles in the oil industry, either on their own or through being acquired by other companies. Standard Oil of New Jersey, the controlling division of Standard Oil at the time of the 1911 breakup, continues to exist as ExxonMobil, formed from the merger of it and Standard Oil of New York. BP has also acquired many Standard Oil descendants, most notably Standard Oil of Ohio and Amoco (Standard Oil of Indiana). Saudi Aramco, the state-owned oil company of Saudi Arabia, also traces its origins to Standard Oil as the Arab kingdom founded it in a partnership with Standard Oil of California, today known as Chevron Corporation. Other companies themselves not primarily focused on the petroleum industry have owned or previously owned Standard Oil descendants, including U.S. Steel (which previously owned Marathon Oil), the first incarnation of DuPont (which previously owned Conoco), and Unilever (which presently owns Chesebrough and Vaseline). Among Standard Oil's largest non-petroleum descendants is the credit bureau TransUnion, which originally was divested from the Standard-descending Union Tank Car Company.