This article is from the Copyright Law FAQ, by Terry Carroll with numerous contributions by others.
In contrast to copyright is "public domain." A work in the public domain
is one that can be freely used by anyone for any purpose.
It used to be that if a work was published without notice, it lost all
copyright, and entered the public domain. That's no longer true, and now
public domain is more the exception than the rule.
There are still a number of ways that a work may be public domain.
- The copyright may have expired (see section 2.4).
- The work might be a work of the U.S. Government; such works
can't be copyrighted (see section 3.6).
- The work might be one that can't be copyrighted. For example,
titles, names, short phrases and slogans can't be copyrighted
(37 C.F.R. 202.1(a)). Note, however, they can be trademarks.
As far as copyright law is concerned, they're public domain,
but as far as trademark law is concerned, they might be
- The copyright might have been forfeited. For example, the work
may have been published without notice prior to the change in
the law that eliminated the notice requirement (March 1, 1988,
the effective date of the Berne Convention Implementation Act,
PL 100-568, 102 Stat. 2853).
- The copyright might have been abandoned. This is pretty rare.
Abandonment requires that the copyright holder intend to
abandon the copyright, and generally requires an unambiguous
statement or overt act on the part of the copyright holder that
indicates his or her intent to dedicate the work to the public
domain. National Comics Pub. v. Fawcett Pub., 191 F.2d 594,
598 (2d Cir., 1951). A statement that anyone who wishes to may
reproduce, perform, or display the work without restrictions
might be sufficient. Simply posting it on a computer network
is not abandonment.
There is a common belief that if someone infringes a copyright, and the
copyright owner does not sue or otherwise put a stop to the infringement,
the copyright is lost and the work goes into the public domain. There is
some pre-1988 law on this (e.g., Stuff v. E.C. Publications, 432 F.2d 143
(2d Cir., 1965) and Transgo v. Ajac Transmission Parts, 768 F.2d 1001
(9th Cir. 1985)), but it seems to derive mostly from the fact that the
copyright holder had acquiesced in the publication of the work without
notice back when notice was a requirement. It was the publication
without notice, and not the lack of enforcement, that actually worked to
put the work in the public domain. This is forfeiture of copyright, not
abandonment. Because the notice requirement is now gone from copyright
law, these cases don't have much weight today.
I can't find anything that supports the idea that failure to assert a
copyright against an infringer can alone lead to placing the work in the
public domain (if you have any authoritative information on this, please
drop me a note at one of the addresses listed in the introduction). Of
course, circumstances may be such that the ability to sue a particular
infringer might be waived (e.g., a statute of limitations may expire (see
section 3.4), or if the infringer has reasonably relied to his or her
detriment on the copyright holder's failure to sue, the doctrine of
laches may bar a suit), but that's only with respect to that particular
infringer, and does not affect the status of the copyright with respect
Sometimes you'll see a program on the network accompanied by a statement
like "This program is public domain. It may be freely distributed, but
you may not charge more for it than the cost of the media." Statements
like these are contradictory. If the program is public domain, you can
do whatever you want with it, including charging whatever you want
(although you might not get it). In this example, what the programmer
really wants to do is to retain the copyright, but provide a non-
exclusive license to copy and distribute the work, with a condition on
the license that only the cost of the media may be charged for it. In
this case, where the programmer has, in two consecutive sentences, both
declared the work to be public domain and asserted a copyright in the
work, it's unpredictable whether a court would interpret this as
If there is any restriction upon the use of the work, even the
restriction that it cannot be sold, the work is not public domain.
Rather, it's copyrighted, and the restrictions are essentially
limitations on a licensee using one or more of the exclusive rights
described above. For example, the restriction that a work may only be
given away for free is a limitation using the distribution right.
Once a work is in the public domain, whether by expiration of copyright
or by expressly being dedicated to the public domain by its copyright
holder, it can never again regain copyrighted status.