public domain, category of creative works that are unprotected by intellectual property law. Since these works cannot be owned, they are free for anyone to use, adapt, reproduce, or distribute for commercial and noncommercial purposes.
Creative work falls into the public domain for a variety of reasons. A work might have been produced before any intellectual property laws were written, as were William Shakespeare’s plays. The length of time during which a work is legally protected might run out, such as the copyright for Herman Melville’s Moby Dick. And some works are exempted from copyright protection altogether, being born into the public domain directly (e.g., mathematical formulas).
The concept of the public domain is valuable to the general welfare because creative material that falls within it lacks any legal or monetary impediment to its full use. This freedom promotes new creativity by allowing any creator to build on the work, furthers education by lowering the cost to access information, improves public health and safety by distributing medical knowledge, and helps to preserve cultural heritage, among other social benefits. Indeed, to some degree a vibrant public domain is required for a society to function. It would not do to have facts, laws, scientific theorems, or short phrases be owned by private individuals. Consequently, the arrival of new creative works in the public domain every year is observed and celebrated by some organizations as Public Domain Day. In most countries, this day falls on January 1.
Theoretically, almost every creative work will eventually enter the public domain. The commonly understood purpose of intellectual property law is to spur innovation by temporarily giving creators the exclusive rights to whatever they invent before that work becomes available for general use. The length of time that creative works are withheld from the public domain varies according to the intellectual property right being reserved and by country. Most countries grant patents to new inventions for up to 20 years, while trademarks may be used indefinitely—although, since trademarks are registered with governments, it is up to each government to decide whether it will recognize a mark. The international standard for copyright protection, enshrined by the Berne Convention, is the duration of the creator’s life plus 50 years, but some countries, such as the United States, have extended that protection by an extra 20 years, largely due to the lobbying efforts of corporate rights holders. These deviations mean that, like trademarks, a work that has fallen into the public domain in one country may have a different status in another.
Countries also differ on whether works in the public domain can be re-copyrighted. The United States has had a two-tiered approach to the issue since 1994, when Congress passed the Uruguay Round Agreements Act (URAA) in order to bring U.S. copyright laws into accord with the Berne Convention. Prior to that year, the law stipulated that a creative work fell into the public domain if its rights holder did not renew the claim with the U.S. Copyright Office. The URAA, however, requires that copyright protection be provided to all creative works by foreign authors so long as those works’ copyright terms have not expired in their countries of origin. As a result, the U.S. government had to remove many foreign works from the public domain while leaving broadly equivalent works of U.S. citizens within it. These retroactive copyrights for foreign works were upheld by the Supreme Court in the 2012 case of Golan v. Holder.
Although most works in the public domain may not be copyrighted again, copyrights for new versions of those works may be granted. Adaptations, translations, and annotated versions of public domain material all qualify for new copyrights, so long as they are sufficiently original. A person may receive the exclusive rights to a new arrangement of public domain material or to photographic reproductions of it, as presentation itself is considered a form of creative expression. A claim to a simple list or table of contents from public documents, however, is unlikely to be accepted.