On 30 July 2019, a Los Angeles jury reached the verdict that Katy Perry’s 2013 hit song “Dark Horse” copied a Christian rap song called “Joyful Noise”.

Despite Katy Perry and her co-writer Dr. Luke’s testimony that they had never heard the song “Joyful Noise”, the jury was persuaded by the plaintiff’s argument that the song was widely disseminated given the fact that “Joyful Noise” had millions of views on YouTube and Myspace and that the song had a degree of critical success (including a Grammy nomination). As a result, the jury found that there was a reasonable possibility that the defendants, who are experienced professional songwriters, had access to the work.

In terms of similarity, the plaintiffs argued that its “descending ostinato 8 figure” instrumental beat was substantially similar to that of “Dark Horse” and that this beat served as “the primary formal building block for both tracks”. In response, the defendants argued that such basic musical patterns are not entitled to copyright protection and that the plaintiffs are effectively trying to own “basic building blocks of music”. Ultimately, the jury sided with the plaintiffs and found that the beat is entitled to copyright protection and that there is substantial similarity between the two songs.  Read more here.