Trade dress law does not protect the appearance of a product design feature (e.g., a product's configuration) against unauthorized copying if the feature is functional, but may protect the appearance if the feature is nonfunctional. The functionality doctrine is intended to preserve competition in the market for a product incorporating a design feature that allegedly is protected by trade dress law, and to avoid conflicts between trade dress law and patent law. The Supreme Court last addressed the functionality doctrine in TrafFix Devices, Inc. v. Marketing Displays, Inc. The Court intended TrafFix to “choke off” anticompetitive trade dress “strike suits.” Unfortunately, TrafFix’s reviews have been terrible.

Some critics complain that TrafFix made it too difficult to protect design features against unauthorized copying, while others claim that it remains too easy to protect them. Much of the debate focuses on whether TrafFix mandated a more restrictive functionality standard for useful design features than for aesthetic design features, and upon the meaning, merits, and application of TrafFix’s standards. However, there is broad critical consensus that TrafFix made the functionality doctrine inconsistent, confusing, and opaque. As one early critic put it, the post-TrafFix doctrine is “a mess.” More recent criticism is in accord.

TrafFix’s critics generally employ conventional interpretive legal scholarship. This Article applies content analysis to data collected from post-TrafFix functionality cases. Content analysis seeks insights based upon an objective and systematic reading of a collective body of case law. The Article employs content analysis to seek insights concerning outcomes under the post-TrafFix functionality doctrine and into how the doctrine operates. The Article emphasizes data from cases concerning motions for summary judgment (SJ Cases) and preliminary injunction (PI Cases). These procedural postures provide important opportunities for courts to apply TrafFix.

The Article proceeds as follows. Part I provides essential background. It defines terminology, discusses burden of proof, and reviews TrafFix’s first principles and functionality standards. Part I also provides analytic and conceptual tools for assessing the post-TrafFix functionality doctrine. These tools include a “two-bar mandate” that is based upon a restrictive reading of TrafFix. Under the mandate, useful design features are subject to a higher functionality bar than aesthetic design features. Part I also describes a “useful/aesthetic continuum” with useful, primarily useful, midcontinuum, primarily aesthetic, and aesthetic reference points. In addition, Part I describes the process of characterizing design features for placement on the continuum. Finally, Part I discusses trade dress law’s “useful-scarcity” and “aesthetic-abundance” principles. These principles aid the characterization process and link the question of character (e.g., useful vs. aesthetic) with the question of functionality (functional vs. nonfunctional).

The Article then turns to the SJ Cases and the PI Cases. Part II reviews summary judgment and preliminary injunction procedures. Part III discusses win/loss records in the SJ and PI Cases. Part IV assesses whether and to what extent these cases were affected by procedural uncertainty, the ambiguity of mixed-character design features, and the willingness of courts to focus the functionality inquiry on the appearance of combinations of design features. Part V concludes the article with final observations concerning the post-TrafFix functionality doctrine and suggestions for improving it. While some critics have suggested that the Supreme Court should or is likely to revisit the functionality doctrine, this Article's suggestions may be implemented without further action by the Court.

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Notes/Citation Information

Journal of Intellectual Property Law, Vol. 17, No. 2 (2010), pp. 321-350



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