Public Domain

The public domain is the set of creative and intellectual works whose exclusive rights have expired, been forfeited, expressly waived, or are inapplicable, leaving the works free for anyone to use, reproduce, adapt, perform, and commercialize without seeking permission. The category covers most works of antiquity, government publications in many countries, and works whose copyright term has lapsed. Term length varies by jurisdiction. The Berne Convention sets a global minimum of life of the author plus 50 years; the European Union, United States, and many others extended this to life plus 70 years. Term extensions have steadily delayed new entries to the public domain; the 1998 U.S. Copyright Term Extension Act is the law upheld in *Eldred v. Ashcroft*, which directly motivated the founding of Creative Commons. Sound recordings, anonymous works, corporate-authored works, and unpublished works typically have separate term rules. Dedicating a still-protected work to the public domain is harder than it sounds. In the United States a clear waiver is generally effective, but in civil-law jurisdictions moral rights and certain neighbouring rights cannot be waived at all. The CC0 tool from Creative Commons addresses this by combining a copyright waiver with a fallback maximally permissive license that takes effect where the waiver itself is not enforceable. The separate Public Domain Mark, introduced in 2010, is a label for works already in the public domain rather than a tool for putting them there. The public domain is essential infrastructure for derivative culture: scholarly editions, public-domain film restorations, classical music recordings, and projects like Project Gutenberg, the Internet Archive, and large parts of Wikipedia depend on it. It also intersects awkwardly with Creative Commons Licensing: a CC license is only meaningful if the underlying work is in copyright, so a CC license applied to a public-domain work has no legal effect on the work itself, only on any new creative contributions.