Can works that have fallen into the public domain be freely used?
Works in the public domain include works that have never been the subject of copyright protection, works whose term of copyright protection has expired, and works by the U.S. government. Works in the public domain may be freely copied and used, and in the case of works with expired copyright terms, used without the former copyright owners’ permission. However, collections, translations and edited versions of works that contain or incorporate works in the public domain may be protected by copyright. The absence of a copyright notice, or the absence of Copyright Office records, does not mean the work is in the public domain and can be used freely.
Works That Are Not the Subject of Copyright Protection
Several types of material are not copyrightable subject matter. According to the U.S. Copyright Office, such uncopyrightable material includes:
Ideas, procedures, processes, systems, methods of operation, concepts, principles, or discoveries;
Typeface or mere variations of typographic ornamentations;
Names, titles, slogans, or other short phrases;
Scènes à faire;
U.S. government works and government edicts; and
It’s important to understand that while these materials are not protectable by copyright, some may be subject to other forms of intellectual property protection, such as patents, trademarks, and trade secrets. See U.S. Copyright Office Compendium Section 707 for more information.
When Copyright Protection Expires
Copyright protection terms vary based on a work’s type, publication status, and date of registration or first publication in the United States. The Cornell University Library Copyright Information Center has compiled a helpful resource on Copyright Term and the Public Domain in the United States to organize this information.
Investigating a Work’s Copyright Status
There are several ways to investigate a work’s copyright status. Generally, you can (1) examine a copy of the work for copyright information such as a copyright notice, publication date, author, or publisher; (2) search the U.S. Copyright Office catalogs and records; and (3) have the U.S. Copyright Office conduct a search for you. There is a fee to have the U.S. Copyright perform a search. Even if you use all three search methods, results may not be conclusive. It is generally safe to assume that a copyrightable work created in the modern era is protected by copyright.
Incorporating Public Domain Elements into Your Work
While anyone can use a public domain work, no one can own it. The selection and arrangement of public domain elements, along with any original elements of your work, may be eligible for copyright protection. But, when you incorporate public domain elements into your work, you do not gain ownership over the individual public domain elements that you used. Other creators are still able to use these public domain elements in their works.