Illinois
How Arnstein v. Porter applies in Illinois: state-specific rules, key cases, and bar exam notes for Copyright.
Illinois law recognizes the framework established in Arnstein v. Porter, allowing for an analysis of copyright infringement focused on originality and substantial similarity. Courts in Illinois commonly apply a two-part test derived from this case.
In Illinois, copyright infringement requires proof that the plaintiff's work is original and that the defendant's work is substantially similar to the plaintiff's work, evaluated from the perspective of an ordinary observer.
The court emphasized the importance of originality and substantial similarity, upholding that the defendant's work was not significantly similar to the plaintiff's.
In a case focused on music copyright, the court acknowledged Arnstein's substantial similarity test, ultimately ruling the works were similar enough to warrant a trial.
The court applied the Arnstein framework to evaluate the similarities in characters, finding insufficient evidence of infringement.
Illinois follows a similar analysis to the federal approach in that both require an evaluation of originality and substantial similarity. However, Illinois courts may place slightly different emphasis on the subjective experience of the ordinary observer as compared to federal interpretations.
The principles from Arnstein v. Porter are relevant on the Illinois bar exam, especially in questions involving copyright infringement and the assessment of originality and substantial similarity.