Derivative works
In copyright law, a derivative work is an expressive creation that includes major copyright-protected elements of an original, previously created first work (the underlying work). The derivative work becomes a second, separate work independent in form from the first. The transformation, modification or adaptation of the work must be substantial and bear its author's personality to be original and thus protected by copyright. Translations, cinematic adaptations and musical arrangements are common types of derivative works.
Most countries' legal systems seek to protect both original and derivative works. They grant authors the right to impede or otherwise control their integrity and the author's commercial interests. Derivative works and their authors benefit in turn from the full protection of copyright without prejudicing the rights of the original work's author.
The Berne Convention for the Protection of Literary and Artistic Works, an international copyright treaty, stipulates that derivative works shall be protected although it does not use the term, namely that "Translations, adaptations, arrangements of music and other alterations of a literary or artistic work shall be protected as original works without prejudice to the copyright in the original work".
An extensive definition of the term is given by the United States Copyright Act in 17 U.S.C. § 101:
A “derivative work” is a work based upon one or more preexisting works, such as a translation, musical arrangement, dramatization, fictionalization, motion picture version, sound recording, art reproduction, abridgment, condensation, or any other form in which a work may be recast, transformed, or adapted. A work consisting of editorial revisions, annotations, elaborations, or other modifications which, as a whole, represent an original work of authorship, is a “derivative work”.
The copyright in a compilation or derivative work extends only to the material contributed by the author of such work, as distinguished from the preexisting material employed in the work, and does not imply any exclusive right in the preexisting material. The copyright in such work is independent of, and does not affect or enlarge the scope, duration, ownership, or subsistence of, any copyright protection in the preexisting material.
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