These resources may be used to search for the copyright status of a work, in particular, whether the work was properly registered or renewed.
- US Copyright Office – home to a variety of online public records related to copyright
- Stanford University’s Copyright Renewal Database – a quick and easy way to determine if older (pre-1964) books are in the public domain due to lack of copyright renewal.
- First Copyright Renewals for Periodicals – a powerful tool for determining whether older (pre-1964) periodicals (magazines, newspapers, etc.) are in the public domain due to lack of copyright renewal.
- U. Penn. Online Books Copyright Registration and Renewal Records – a helpful collection of links to online copyright registration and renewal records published in a variety of places online, as well as guides to searching these resources.