If a work is in the public domain, that means you do not need any permissions or copyright exceptions to use it freely. Works in the public domain include:
- The copyright term has expired
- Works so old they were never under copyright
- Copyright was improperly renewed
- The author has waived all copyright restrictions
- Publication by a government agency
- Laws that have been enacted by a local, state, or federal government
- Works not subject to copyright or other intellectual property protections (patent, trademark). For example, ideas themselves cannot be copyrighted, just their expression on a page.
If it meets one of the following criteria, it is most likely in the public domain:
- Works published in or before 1923
- Works published prior to 1964 where copyright was not renewed (renewal was a requirement until 1978)
- Works published prior to March 1, 1989 that do not include a proper copyright notice (the (c) symbol)
- Facts or ideas (although the specific way these facts or ideas are written down is subject to copyright)
If you're ever unsure, ask a librarian for help!
