The Sherman Antitrust Act became law in the United States in 1890.
Congress passed the act during the 51st Congress, and President Benjamin Harrison signed it on July 2, 1890. It was named for Senator John Sherman of Ohio, who was its principal author. The law sought to preserve competition by prohibiting contracts, combinations, and conspiracies that restrained interstate or international trade.
The act also targeted monopolization and attempted monopolization. Its broad language made it an important foundation of U.S. competition law, although courts initially interpreted and enforced it unevenly. Later antitrust legislation, especially the Clayton Antitrust Act of 1914 and the Federal Trade Commission Act, strengthened and clarified the federal framework.
The year 1914 is therefore a frequent mix-up: it marks major additions to antitrust law, not the Sherman Act itself. The statute was later officially redesignated as the Sherman Act, but its original enactment date remains 1890.