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Substantial Similarity

Illustrates the "substantial similarity" doctrine from U.S. copyright law, using a set of case summaries.

Nichols v. Universal Pictures Corp., 45 F.2d 119 (2d Cir. 1930).


The plaintiff wrote the play “Abie’s Irish Rose.” The defendant produced the motion picture “The Cohens and The Kellys.” The plaintiff alleged that the defendant's movie infringed plaintiff’s copyright. Both stories feature a Jewish family and an Irish Catholic family. In the stories, the fathers try to stop their children from marrying each other. Both stories end in reconciliation. There was no literal copying of names, dialogues or scenes. The question was whether defendant’s use of “an abstract of the whole” of plaintiff’s play constituted infringement. The Second Circuit wrote that, “the controversy chiefly center[ed] upon the characters and sequence of incident.”

Procedural Notes

The Second Circuit concluded that expert testimony should be excluded, because the issue of similarity was not intricate or complex. Otherwise, the expert testimony would prolong the trial. It could also distract the court from plainly comparing the works at issue.

Court's Analysis

The Second Circuit held that there was no substantial similarity between the two works.

The court noted that it is challenging for courts to decide when non-literal copying is infringing. Judge Learned Hand laid out his famous “abstraction test” to help find the line between a work’s unprotectable ideas and its protectable expressions:

Upon any work, and especially upon a play, a great number of patterns of increasing generality will fit equally well, as more and more of the incident is left out. The last may perhaps be no more than the most general statement of what the play is about, and at times might consist only of its title; but there is a point in this series of abstractions where they are no longer protected, since otherwise the playwright could prevent the use of his "ideas," to which, apart from their expression, his property is never extended.

Applying the test, the court found that the plots of the works were sufficiently different. The plaintiff’s work tells the story of religious strife between two families. The quarrels end thanks to the grandchildren. By contrast, the defendant’s work is about the personal conflicts of the two families. The conflicts are further fueled by the Jewish family’s newly acquired riches. The two families in the defendant’s work reconcile because the Jewish father is honest. Grandchildren don’t appear in the defendant’s work. The plaintiff’s copyright does not extend to the general plot idea.

Neither does copyright law protect basic characters and stock figures. Some characters are similar in their most basic descriptions. However, they are quite different in their particulars. For example, the Jewish father in the plaintiff’s play is “affectionate, warm and patriarchal.” In the defendant’s movie he is “tricky, ostentatious and vulgar.” The court concluded the similarities were ideas too generalized to be copyrightable.

Works at Issue

Abie's Irish Rose

The Cohens and the Kellys

According to an entry in the Library of Congress Performing Arts Databases, "The Cohens and the Kellys" is held at the Cinematheque Royale de Belgique (Brussels), and the Museum Of Modern Art (New York).