A public domain work is a creative work that is not protected by copyright and which may be freely used by everyone. Works fall into the public domain for three main reasons:

1. the term of copyright for the work has expired;

2. the author failed to satisfy statutory formalities to perfect the copyright or

3. the work is a work of the U.S. Government.

As a general rule, most works enter the public domain because of old age. This includes any work published in the United States before 1923. Another large block of works are in the public domain because they were published before 1964 and copyright was not renewed. (Renewal was a requirement for works published before 1978.) A smaller group of works fell into the public domain because they were published without copyright notice (copyright notice was necessary for works published in the United States before March 1, 1989).

Use the very neat Copyright Slider Tool to determine is a work is still protected by copyright.

This 1945 United States Office of War Information poster is an example of a public domain item. Materials published by the U.S. Government Printing Office are in the public domain and, as such, not subject to copyright restrictions. Anyone can reproduce and use it. Click on the picture for a larger version.

The image is courtesy of Northwestern University's digital collections

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