## Facts

- Ira B. Arnstein, a professional songwriter, claimed that several Cole Porter songs infringed Arnstein’s copyrighted musical compositions.
- Arnstein sought damages only, making the case an action at law with a timely jury demand.
- Porter moved for summary judgment under Federal Rule of Civil Procedure 56.
- The district court granted summary judgment for Porter, relying heavily on expert musical testimony finding insufficient similarity.
- Arnstein appealed, arguing he was improperly denied a jury determination on infringement.

## Issues

1. Whether summary judgment was proper where infringement turned on disputed facts about copying and whether ordinary listeners would perceive unlawful appropriation.
2. How to structure musical copyright infringement analysis regarding (a) factual copying and (b) unlawful appropriation, including the role of expert testimony versus lay perception.

## Decision

- The Second Circuit reversed and remanded for a jury trial.
- The court held that infringement analysis requires two separate determinations: (1) whether the defendant copied the plaintiff’s work and (2) whether any copying amounted to unlawful appropriation.
- The court ruled that expert analysis may assist on factual copying, but improper appropriation turns on the reaction of ordinary lay hearers.
- The court concluded it could not say the similarities were so minimal that a directed verdict (or summary judgment) for Porter would be proper on misappropriation, even if some of Arnstein’s broader allegations appeared implausible.

## Legal Principles

- Copyright infringement requires proof of (1) factual copying and (2) improper (unlawful) appropriation.
- Copying may be shown by direct evidence or circumstantial evidence such as access plus probative similarities; absent access, similarities must be so striking as to preclude independent creation.
- Expert testimony and analytic dissection are relevant to the copying inquiry.
- Improper appropriation is assessed by the response of ordinary lay listeners; expert testimony and dissection are not controlling on that question.
- Summary judgment is inappropriate where credibility, disputed inferences, or lay audience reaction are material to whether protected expression was unlawfully taken.

## Conclusion

The Second Circuit required a jury trial because musical infringement claims must be separated into factual copying and lay-audience improper appropriation, and the district court could not resolve the latter by expert affidavits on summary judgment.


Arnstein v. Porter, 154 F.2d 464 (2d Cir. 1946)