Our Bizarre System for Proving Copyright Infringement
Mark A. Lemley · 2016
At the heart of copyright infringement cases is “substantial similarity”between the plaintiff’s and the defendant’s works. But while every circuitagrees on the centrality of substantial similarity, that basic agreementconceals surprising differences in what exactly we mean by substantialsimilarity and how it is to be proven in court. And the majority approach,defined by the Second Circuit in Arnstein v. Porter and the Ninth Circuitin Sid and Marty Krofft, has the analysis of proof exactly backwards –permitting analytic dissection of the works and expert testimony where thequestion is one that should be handed to the members of the jury, andfalling back on the “ordinary observer” test on the very questions thatrequire careful dissection by the court. I argue that the Arnstein andKrofft tests make no sense. A better model draws from software copyrightcases, which give filtration and dissection of unprotectable elements amore central role.