Finding the Copyright Status of a Work
This is a very complex task, but a quick look at the Cornell Copyright Term Chart may help clarify this process. Works published in the United States before 1923 have generally lost copyright protection and may be freely copied.
Between 1923 and 1963, authors of works published in the United States were required to renew their copyright 28 years after publication. If the author failed to renew the copyright, the work has fallen into the public domain. If the author did register and renew the copyright, the work is still copyrighted today. Renewals and registrations since 1978 can be found through an online search at the copyright.gov website. Searches for registrations and renewals before 1978 may be conducted in the Catalog of Copyright Entries. The Herman B. Wells library has a copy of the Catalog (Call Number: Z642 .U69 ) on the 11th floor. For book renewals before 1978, Stanford's Copyright Renewal Database provides a quick searchable web interface to find copyright renewals.
Beginning in 1964, if an item was published with a copyright notice, all copyrights were automatically renewed, and nothing copyrighted since then has fallen into the public domain.
Unpublished works have separate terms and are given special consideration. Again, see the Cornell Copyright Term Charfor an overview.
US Government Publications
According to § 105 of the Copyright Law, copyright protection is not available for any work produced by an employee of the United States Government in the course of their work duties. Exceptions are available for certain works of the National Institute for Standards and Technology (NIST) and the U.S. Postal Service. Section 105 does NOT apply to state, local, or foreign government publications, only federal government works.
Please keep in mind that US government publications may include a report, photo, or other material from a non-governmental employee and therefore that portion of the publication may be covered by copyright protections.