Transformative

In United States copyright law, transformation is a possible justification that use of a copyrighted work may qualify as fair use, i.e., that a certain use of a work does not infringe its holder's copyright due to the public interest in the usage. Transformation is an important issue in deciding whether a use meets the first factor of the fair-use test, and is generally critical for determining whether a use is in fact fair, although no one factor is dispositive.

In United States patent law the term also refers to the test set in In re Bilski: that a patent-eligible invention must “transform a particular article into a different state or thing.”

Like most of the modern fair use doctrine, the doctrine of transformation was heavily influenced by the 1841 circuit court case Folsom v. Marsh. In that case, Justice Story ruled that

if [someone] thus cites the most important parts of the work, with a view, not to criticize, but to supersede the use of the original work, and substitute the review for it, such a use will be deemed in law a piracy.

The standard of "supersed[ing] the use of the original work" would be widely cited as a standard for the degree to which a work was transformative when fair use had become more clearly fixed as a legal principle.

In the Copyright Act of 1976, Congress defined fair use explicitly for the first time, giving as one factor "the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes". This factor was later determined to hinge in substantial part on transformation. See, e.g., Campbell v. Acuff-Rose Music, a case in the United States Supreme Court:

Under the first of the four 107 factors, "the purpose and character of the use, including whether such use is of a commercial nature ...," the inquiry focuses on whether the new work merely supersedes the objects of the original creation, or whether and to what extent it is controversially "transformative," altering the original with new expression, meaning, or message. The more transformative the new work, the less will be the significance of other factors, like commercialism, that may weigh against a finding of fair use.

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