In a typical case of trademark infringement, a plaintiff must show, among other things, that potential consumers would be confused as to the source of a good or service, due to the defendant’s use of a mark (or in the case of trade dress infringement, the same or similar product packaging, design, labeling, etc.) that creates confusion as to source, sponsorship, or affiliation. This inquiry into the likelihood of confusion is most often governed by multifactor tests, the most prominent of which is the test articulated in Polaroid Corp. v. Polarad Electronics Corp. by the U.S. Court of Appeals for the Second Circuit. The Second Circuit is of particular interest to those who study trademark law as it generates the greatest number of trademark infringement opinions. In the Polaroid test, eight factors are considered, including: the strength of the original user’s mark, similarity of the marks, proximity of the products, the likelihood that the original user would enter into the alleged infringer’s market (thus, “bridging the gap” between the two markets), evidence of actual confusion, the alleged infringer’s intent, the relative quality of the products bearing the marks in question, and sophistication of the consumers of the products.
Professor Barton Beebe, in his empirical analysis of multifactor tests for trademark infringement nationwide, found that judges “employ ‘fast and frugal’ heuristics to short-circuit the multifactor analysis” and challenged the conventional wisdom that no single factor in the multifactor test is dispositive. However, the limited temporal scope of his inquiry (2000−2004) raises the question of whether his results are typical for trademark cases or just a five-year anomaly. This paper attempts both to determine whether Beebe’s findings hold true over a longer, fifteen-year period and to discover any new information that sheds light on how judges decide trademark cases. Part I.A describes our methodology while Part I.B provides background statistics on our data set. Part II presents analysis of factor correlation, outcome classification trees, stampeding, and each individual factor, including comparison with Beebe’s results, as well as description of historical trends in our data. Part III analyzes the effect of other considerations related to the multifactor test—whether or not the products are in competition, whether the party names are the trademarks at issue, whether the court indicates one factor can be dispositive of the outcome, and whether or not the court considers factors in addition to those listed in the Second Circuit’s Polaroid test.