Rockefeller, along with his associates Samuel Andrews and Henry M. Flagler, founded Standard Oil in 1870. Within two years, the company had a monopoly on the refinement of oil in the Cleveland area. In 1881, the company was reorganized as a first-of-its-kind trust, allowing it to quickly expand by either building or buying up oil pipelines and other infrastructure. By 1882, it had a virtual monopoly on the oil business in the U.S. The federal government disapproved of the situation, and Congress passed the Sherman Antitrust Act in 1890 to break up Standard Oil. A running battle ensued, which the government finally won in a Supreme Court ruling in 1911. Thus, Standard Oil essentially existed as a national monopoly for 19 years.