Finding the Public Domain

Works enter the public domain in a few key ways:

  • most commonly, their term of protection expires
  • less commonly, if they fail to comply with certain formalities
  • they are authored by the federal government

If you’d like to know whether a particular work is in the public domain, it will be helpful to know, for starters:

  • whether it was published, and if so, when;
  • for unpublished works and works made after 1977, who was the author, have they died, and if so, when; and
  • in what country was the work first published?

Once you gather that basic information, a good place to start is the Cornell Library’s Copyright Term and the Public Domain in the United States page. First created by Peter Hirtle and updated regularly by the Cornell University Library, the page distills many pages of complex law into a remarkably readable chart.

One more variable that will rear its head, for works first published between 1924 and 1964, is the question whether a work had its copyright renewed after it’s initial 28-year term. Many works were not renewed and rose into the public domain decades ago, but a thorough search of the renewal records is required to determine if this is the case for any particular work. To learn more, see John Mark Ockerbloom’s excellent guide to researching renewal.

The web contains a panoply of additional information on the public domain, as do any number of books. Be careful as you explore, however. Most importantly, watch out for books that treat 1923 as a significant year—starting in 2019, that year is no longer significant. “Published more than 95 years ago” has replaced “published prior to 1923” as the useful rule of thumb for judging whether an older work is in the public domain.