The audience in intellectual property infringement.

• Author: Fromer, Jeanne C.
• Position: Abstract through I. Audiences in IP Cases C. Copyright Law, p. 1251-1273

Every intellectual property ("IP") right has its own definition of infringement. In this Article, we suggest that this diversity of legal rules is largely traceable to differences in the audience in IP cases. Patent, trademark, copyright, and design patent each focus on a different person as the fulcrum for evaluating IP infringement. That patent law, for example, focuses on an expert audience while trademark looks to a consumer audience explains many of the differences in how patent and trademark cases are decided. Expert audiences are likely to evaluate infringement based on the technical similarity between the plaintiffs and defendant's works. Consumers, by contrast, are likely to pay more attention to market substitution and less attention to how things work under the hood. Understanding the different audiences in IP infringement is critical to understanding how the IP regimes variously define infringement.

The focus on audience has normative as well as descriptive implications. Neither patent law, with its focus on experts and technical similarity, nor trademark law, with its market-based consumer focus, has it entirely correct. Rather, we suggest that as a general matter, infringement of an IP right should require both technical similarity and market substitution. An ideal IP regime should care about a defendant's conduct only if that conduct actually causes injury to the plaintiffs market and its work is sufficiently like the plaintiffs that it is reasonable to give the plaintiff control over that work. Assessing infringement through the expert's eyes ensures that the law prevents closely related works in the field while permitting sufficiently different contributions. The consumer vantage point ensures that we protect IP owners only when they have been harmed in the marketplace.

IP owners who want to show infringement should have to demonstrate both that the defendant's work is technically similar to their own from the expert's vantage point and that the defendant's use causes the plaintiff harm in the marketplace. Copyright law, which looks to both experts and consumers at various points in the infringement analysis, is on the right track.

TABLE OF CONTENTS INTRODUCTION I. AUDIENCES IN IP CASES A. Trademark Law B. Patent Law C. Copyright Law D. Design Patent Law II. POSSIBLE INFRINGEMENT AUDIENCES A. Consumer B. Expert C. Ordinary Reasonable Person III. THE CONSUMER AND THE EXPERT AS TOUCHSTONES A. Experts and Technical Similarity B. Consumers and Market Substitution C. Testing Both Technical Similarity and Market Substitution 1. Bringing Market Substitution to Patent Law 2. Mandating Similarity in Trademark Law 3. Copyright's Hybrid 4. A Missed Opportunity: Design Patents CONCLUSION INTRODUCTION

At the heart of any IP case is the problem of deciding whether the defendant has infringed on the plaintiff's right. A principal question in IP infringement disputes is whether the defendant's product (or work, or brand, or idea) is too similar in some respect to the plaintiff's.

But who decides whether the defendant's product is too similar to the plaintiff s? Put another way, who is the audience in IP infringement? Is it the customer of the parties' products that must find the products too similar? Or perhaps an expert on the products' subject matter? Or instead an ordinary reasonable person? This choice can easily affect the judgment on similarity. For example, a chemist might think that two drugs for providing pain relief are not sufficiently similar because of their different chemical composition or because they trigger a different pathway in the human body. A customer, by contrast, might find the two drugs highly similar because they provide comparable relief without side effects. An ordinary reasonable person might find insufficient similarity between two audiovisual works that are both aimed at children and depict fantasylands filled with fanciful creatures because a principal character in one work wears a "cummerbund," while a major character in the other wears a "diplomat's sash." By contrast, the typical child encountering the works would regard them as substantially similar. (1) A musicologist might ignore differences in musical style, instead focusing on the underlying composition, in determining whether a pop song is similar to a calypso song. A consumer would do just the opposite. (2) Consumers may focus on descriptive similarities in brand names or functional aspects of packaging that producers do not intend to indicate the product's source. (3)

As these examples illustrate, the choice of audience to decide similarity matters because it affects whether infringement is found, which in turn influences the sorts of works that third parties are willing to produce without risking liability. Choice of audience thus collectively shapes the available body of works, products, and brands. This critical link between the audience for IP infringement and the types of works the law permits underscores the importance of the optimal choice of audience. (4) But surprisingly, the question of the audience for IP infringement has largely been ignored in the academic literature (5) and undertheorized in judicial decisions. (6)

Curiously, each IP regime offers a different answer to the audience question. Patent law generally seeks the opinion of a hypothetical expert, the person having ordinary skill in the art ("PHOSITA"). Trademark law takes the opposite approach, principally asking what consumers in the real world think. Copyright law seems to employ aspects of each approach, switching off between seeking the perspective of experts, consumers, and ordinary observers. And design patent law traditionally applied a hybrid approach but has recently switched to a consumer-focused inquiry. (7)

As we explain in this Article, the current hodgepodge of audiences in IP infringement cases reflects a lack of deliberation over what ought to be defined as infringement. Each regime's choice of audience drives its definition of infringement, which in turn determines how well the IP regime achieves its goals. Take patent law's focus on experts. Experts are likely to find infringement when two items are technically similar, whether or not consumers would view them as market substitutes. As a result, patent law tends to find infringement whenever two products are sufficiently similar technically, without regard to the market relationship between the products. Trademark and design patent law, by contrast, focus on the consumer audience. Consumers are likely to find similarity when two works are market substitutes; they don't usually care what is under the hood. So trademark and design patent law tend to find infringement when two products satisfy the same market need or desire, whether or not that market substitution results from the technical similarity of the protected product's novel attributes. Copyright law takes a hybrid approach, asking some questions from the perspective of an expert and others from the perspective of either a consumer or a reasonable "ordinary observer." As a result, copyright sometimes seems to pay attention to technical similarity and other times to focus on market substitution.

The first goal of our Article is descriptive. We think that a focus on the audience in IP infringement--and a recognition that each IP regime has a different audience in mind--helps explain why four legal regimes with related goals (8) have nonetheless chosen such different means of testing infringement.

But our focus on the audience has a normative payoff as well: it causes us to ask in a more general way what IP laws should define as infringement. We think copyright's hybrid model hints at the right approach. In this Article, we argue that each of the IP regimes--patent, copyright, trademark, and design patent--should find infringement only when the defendant's product is too similar to the plaintiff's in the eyes of both experts and consumers, not just one or the other. Put another way, infringement in an ideal IP regime grounded in utilitarianism should require proof of both sufficient technical similarity and market substitution. Market substitution is important because a use that does not interfere with the plaintiff's market in some way generally does no relevant harm. (9) Technical similarity is also important because not all acts that interfere with a plaintiff's market are problematic. A defendant who enters the market with a...