Sherman Anti-Trust Act (1890)
Based on Congress’s power under the Commerce Clause, this Act put limits on certain economic rights and was the first attempt by Congress to limit monopolies. It gave Congress the power to investigate and dissolve contracts or business combinations (mergers) that restrained interstate or foreign trade or commerce. The lawsuit that broke up telecommunications company AT&T in 1982 was filed under the Sherman Anti-Trust Act.
This law was used successfully by President Theodore Roosevelt in what he called his “trust-busting” campaigns, and by President William Howard Taft against the Standard Oil trust and the American Tobacco Company.