It was not until a full 180 years after its establishment that it was significantly extended beyond that, in Copyright Act of 1976 to "Either 75 years or the life of the author plus 50 years" and the Sonny Bono Copyright Term Extension Act of 1998 (also called the "Mickey Mouse Protection Act", because it prevented the copyright from expiring on the first commercial success of the cartoon character Mickey Mouse), which increased it even more, to 120 years, or the life of the author plus 70 years. 40 years later, the initial term was changed to 28 years. The length of copyright established by the Founding Fathers was short, 14 years, plus the ability to renew it one time, for 14 more. US copyright law traces its lineage back to the British Statute of Anne, which influenced the first US federal copyright law, the Copyright Act of 1790. Main article: History of copyright law of the United States
These exclusive rights are subject to a time limit, and generally expire 70 years after the author's death or 95 years after publication. With the stated purpose to promote art and culture, copyright law assigns a set of exclusive rights to authors: to make and sell copies of their works, to create derivative works, and to perform or display their works publicly. The copyright law of the United States grants monopoly protection for "original works of authorship".