Wikipedia:Non-U.S. copyrights

It is not always simple to determine the copyright status of a work first published outside of the United States. To determine the copyright status of a work in its country of origin (and there are at least 192 different national copyright régimes) it is typically necessary to know the date of death of the author, while to determine the copyright status in the United States it is typically necessary to know its publication history and its copyright status in the country of origin not on the date of uploading but on January 1, 1996.

This page does not apply to works first published in the United States.

A work can be in the public domain in the United States but still under copyright protection in its "source country": this is the case, for example, for Einstein's paper describing the theory of special relativity, first published in Germany in 1905. Any work published before 1923 is in the public domain in the United States, regardless of its source country, but German copyright protection lasts for seventy years after the death of the author (post mortem auctoris or "pma"), until December 31, 2025 in this case.

A work can equally be in the public domain in its source country but still under copyright in the United States: any non-posthumous work published after 1922 by a British or German author who died between January 1, 1926 and December 31, 1946 falls into this category. The copyright term of 70 years after the author's death (which applies to all European Union countries) has expired, but its U.S. copyright was restored on January 1, 1996 by Act of Congress and will run until at least December 31, 2018 (95 years after publication, rounded up to the end of the year).

Works first published outside the United States may be protected under U.S. copyright either through restoration of the copyright or through a copyright that subsists from the time of publication. The case of restored copyrights will be examined first, as it also determines the copyright status of most contemporary works.

A large number of non-U.S. works were given copyright protection in the United States by the Uruguay Round Agreements Act of 1994 (URAA) as a result of the Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS). These copyrights are known as "restored copyrights", even though some of the works had never previously been protected in the United States. The countries concerned by this measure are (in practice) either:

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