Arnstein v. Porter
Arnstein v. Porter, 154 F.2d 464 (2d Cir. 1946)[1] is a case in the law of copyright in the United States which set a precedent for determining substantial similarity for copyright infringement.
Facts
Ira B. Arnstein, a chronic litigator,[2] sued Cole Porter for copyright infringement. Arnstein was a professional songwriter and had published several popular songs. He claimed Porter had plagiarized some of his songs, mainly "The Lord is My Shepherd" and "A Mother's Prayer." Porter rebutted, arguing he had never heard Arnstein's songs and he had independently created the songs. Arnstein argued Porter enlisted spies or "stooges" to steal the songs. Porter filed for summary judgment.
The trial court granted summary judgment requested by Porter. The court had relied on expert testimony about the similarity of the songs and found that Porter's songs were not substantially similar. Arnstein appealed.
Opinion
The appellate court reversed and remanded. The court stated there are two elements to establish infringement: 1) there must be evidence that the defendant had access to the copyrighted work, and; 2) there must be evidence that the works are substantially similar.
The court stated "the testimony of experts may be received to aid the trier of the facts," clarifying that expert testimony is allowed on cases dealing with copyright of songs. The court also stated that in the absence of direct evidence of copying, "the similarities [between the works] must be so striking as to preclude the possibility that plaintiff and defendant independently arrived at the same result."
Ultimately, the court found that whether two songs were substantially similar enough to constitute copyright infringement was a matter of fact for a jury to decide, so they remanded the case for a jury trial.