How to use the Public Domain

Derivative works include translations, musical arrangements, and dramatizations of a work, as well as other forms of transformation or adaptation.
 
Copyrighted works may not be used for derivative works without permission from the copyright owner, while public domain works can be freely used for derivative works without permission.

Artworks that are public domain may also be reproduced photographically or artistically or used as the basis of new, interpretive works.
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Once works enter into the public domain, derivative works such as adaptations in book and film may increase noticeably, as happened with Frances Hodgson Burnett’s novel The Secret Garden, which became public domain in 1987

 As of 1999, the plays of Shakespeare, all public domain, had been used in more than 420 feature-length films. In addition to straightforward adaptation, they have been used as the launching point for transformative retellings such as Tom Stoppard’s Rosencrantz and Guildenstern Are Dead and Troma Entertainment’s Tromeo and Juliet. Marcel Duchamp’s L.H.O.O.Q. is a derivative of Leonardo Da Vinci’s Mona Lisa, one of thousands of derivative works based on the public domain
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