-U.S. Constitution: Article I, Section 8, Clause 8
Copyright Act of 1790 established first U.S. copyright law with term of 14 years with 14-year renewal
Copyright Act of 1909 extended term to 28 years with 28-year renewal
Copyright Act of 1976 extended term to either 75 years or life of author plus 50 years
Sonny Bono Copyright Term Extension Act of 1998 extended terms to 120 years for corporations or life plus 70 years for individuals
Digital Millennium Copyright Act of 1998 criminalized circumventing DRM (Digital Restrictions Management) even when no actual copyright infringement occurs. Also made internet service providers and websites responsible for the actions of their users.
