Eldred v. Ashcroft, 537 U.S. 186 (2003), was a decision by the Supreme Court of the United States upholding the constitutionality of the 1998 Sonny Bono Copyright Term Extension Act (CTEA). The practical result of this was to prevent a number of works from entering the public domain in 1998 and following years, as would have occurred under the Copyright Act of 1976. Materials which the plaintiffs had worked with and were ready to republish were now unavailable due to copyright restrictions.

The Sonny Bono Copyright Term Extension Act – also known as the Copyright Term Extension Act, Sonny Bono Act, or (derisively) the Mickey Mouse Protection Act – extended copyright terms in the United States in 1998. It is one of several acts extending the terms of copyright.