The foreign works at issue in Golan v. Holder had fallen into America’s public domain for various reasons: Either the U.S. had no copyright relations with the author’s home country, the author failed to satisfy U.S. copyright formalities (e.g., failed to register for protection) or the work was uncopyrightable at the time under U.S. law (i.e., the work was a sound recording, which was uncopyrightable here until Congress changed the law in 1972).
The U.S., however, was obligated, as a member of the Berne Convention, to overlook those problems and provide copyright protection to those works. Berne mandates that a work created by an author in any member state must receive copyright protection in all member states. Moreover, such protection must last until the full copyright term has expired in either the country where protection is claimed or the work’s country of origin.
The U.S. ignored this treaty obligation, however, because Berne lacked a serious enforcement mechanism.
The situation changed in 1994, when the U.S. signed onto the treaties establishing the World Trade Organization (WTO). Those treaties required all signatories to comply with Berne or face significant penalties. Soon after the U.S. joined the WTO, Congress enacted the Uruguay Round Agreements Act and satisfied America’s obligations under Berne.