The public performance or display of a work with no copies made does not constitute publication. For current information on when works now pass into the public domain, see Laura Gasaway's web site at the University of North Carolina. Published works dating from 1964-77 will not fall into public domain until at least 2059. The fact that a book is out of print and the copyright holder cannot be located does not waive its copyright protection. Public Domain Public domain works may be freely used in teaching, research, and any other form of scholarship.
Works can enter the public domain several ways.
This is not an all-inclusive list. Expiration of copyright. Works become public domain when their terms of copyright protection expire. Federal Government authorship. With the exception of some reference data published by the U.S. Department of Commerce, materials published by the U.S. Federal Government are specifically excluded from copyright protection and are in the public domain from the date of creation.