Copyright and Fair Use

A public domain work is a creative work that is not protected by copyright and which may be freely used by everyone.

Stanford University Libraries provides a detailed description of public domain with links to freely-available online resources.

Works are in the public domain for four main reasons:

1. The term of copyright has expired.
2. The creator failed to properly establish initial copyright ownership or to follow copyright renewal rules.
3. The copyright owner may choose to place a work in the public domain by including a statement such as "This work is dedicated to the public domain."
4. Publications of the U.S. Government are in the public domain.

For a detailed view of which works could be considered in the public domain, see Copyright Term and the Public Domain in the United States.

Works published before 1977 without the copyright notice © are in the public domain.

Unpublished works pass into the public domain 70 years after the death of the author.  As an example for 2015, works created by an author who died prior to 1944 are in the public domain. The estate of a deceased author cannot control the work after this time period.

A work created by a corporation or an unknown author passes into the public domain 95 years after publication.