What US federal law protects trademarks?

The Lanham Act is the U.S. federal law that protects trademarks. Formally called the Trademark Act of 1946, it created the modern federal framework for trademark registration and infringement claims.

President Harry Truman signed the law on July 5, 1946, and it took effect one year later. Before it, trademark protection relied heavily on state common law and earlier federal statutes that had proved incomplete. The act is named for Representative Fritz G. Lanham of Texas.

The law is administered through the U.S. Patent and Trademark Office’s registration system. It also gives trademark owners legal remedies against infringement, dilution, false advertising, and certain forms of cybersquatting. Section 43(a), for example, is widely used in disputes involving unregistered marks, trade dress, and misleading commercial representations.

A common mix-up is confusing trademarks with patents and copyrights. Patents protect inventions, while copyrights protect original expressive works. Trademark rights instead identify the commercial source of goods or services and can continue as long as the mark is used and renewal requirements are met.