The McCarran–Ferguson Act, 15 U.S.C. §§ 1011-1015, also known as Public Law 15, is a United States federal law that exempts the business of insurance from most federal regulation, including federal antitrust laws to a limited extent. The McCarran–Ferguson Act was passed by the 79th Congress in 1945 after the Supreme Court ruled in United States v. South-Eastern Underwriters Association that the federal government could regulate insurance companies under the authority of the Commerce Clause in the U.S. Constitution.