Two Centuries of Trademark and Copyright Law: A Citation-Network-Analysis Approach

The Supreme Court has decided many more patent cases than trademark or copyright cases. This is so not just in the past decade—the focus of the tenth annual Supreme Court IP Review at the Chicago-Kent College of Law, in September 2019, at which I presented this research—but in the past 20 decades. In gathering the entire body of the Court’s i.p. caselaw, for a study with citation-network-analysis tools, I found that patent cases greatly outnumber trademark and copyright cases. Moreover, patent cases, especially patent & antitrust cases, dominate the metrics for the most central cases in the citation network. One can, however, take the Court’s trademark and copyright cases out of the shadow of the patent cases, creating a citation network focused on those areas of i.p. law. This paper does so. Specifically, I focus on the basic citation and co-citation networks embedded in all the Supreme Court trademark and copyright cases that cite out to one or more prior Supreme Court cases in any doctrinal area. These i.p. cases run from Stevens v. Gladding, 58 U.S. (17 How.) 447 (1855), to, most recently, Mission Product Holdings, Inc. v. Tempnology, LLC, 139 S. Ct. 1652 (2019). The lesson is as clear as it is brief: trademark dominates the jurisprudence through 1972, then copyright dominates from 1973 to the present.