McCarran–Ferguson Act

The McCarran–Ferguson Act, 15 U.S.C. §§ 1011-1015, is a United States federal law that exempts the business of insurance from most federal regulation, including federal anti-trust laws to a limited extent. The McCarran–Ferguson Act was passed by 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.

The McCarran–Ferguson Act does not itself regulate insurance, nor does it mandate that states regulate insurance. "Acts of Congress" that do not expressly purport to regulate the "business of insurance" will not preempt state laws or regulations that regulate the "business of insurance."

The Act also provides that federal anti-trust laws will not apply to the "business of insurance" as long as the state regulates in that area, but federal anti-trust laws will apply in cases of boycott, coercion, and intimidation. By contrast, most other federal laws will not apply to insurance whether the states regulate in that area or not.