The big question is whether transformative use is used too much...or not enough. Clark Asay (BYU) has done the research on this so you don't have to. In his forthcoming article in Boston College Law Review called, Is Transformative Use Eating the World?, Asay collects and analyzes 400+ fair use decisions since 1991. The draft is on SSRN, and the abstract is here:
Fair use is copyright law’s most important defense to claims of copyright infringement. This defense allows courts to relax copyright law’s application when courts believe doing so will promote creativity more than harm it. As the Supreme Court has said, without the fair use defense, copyright law would often “stifle the very creativity [it] is designed to foster.”
In today’s world, whether use of a copyrighted work is “transformative” has become a central question within the fair use test. The U.S. Supreme Court first endorsed the transformative use term in its 1994 Campbell decision. Since then, lower courts have increasingly made use of the transformative use doctrine in fair use case law. In fact, in response to the transformative use doctrine’s seeming hegemony, commentators and some courts have recently called for a scaling back of the transformative use concept. So far, the Supreme Court has yet to respond. But growing divergences in transformative use approaches may eventually attract its attention.
But what is the actual state of the transformative use doctrine? Some previous scholars have empirically examined the fair use defense, including the transformative use doctrine’s role in fair use case law. But none has focused specifically on empirically assessing the transformative use doctrine in as much depth as is warranted. This Article does so by collecting a number of data from all district and appellate court fair use opinions between 1991, when the transformative use term first made its appearance in the case law, and 2017. These data include how frequently courts apply the doctrine, how often they deem a use transformative, and win rates for transformative users. The data also cover which types of uses courts are most likely to find transformative, what sources courts rely on in defining and applying the doctrine, and how frequently the transformative use doctrine bleeds into and influences other parts of the fair use test. Overall, the data suggest that the transformative use doctrine is, in fact, eating the world of fair use.
The Article concludes by analyzing some possible implications of the findings, including the controversial argument that, going forward, courts should rely even more on the transformative use doctrine in their fair use opinions, not less.In the last six years of the study, some 90% of the fair use opinions consider transformative use.* This doesn't mean that the the reuser won every time - quite often, courts found the use to not be transformative. Indeed, while the transformativeness finding is not 100% dispositive, it is highly predictive. This supports Asay's finding that transformativeness does indeed seem to be taking over fair use.