In May 2020—over two years before OpenAI launched ChatGPT—the media and technology conglomerate Thomson Reuters sued ROSS Intelligence, a small artificial intelligence (AI) startup, alleging copyright infringement. ROSS was developing an AI-driven legal research platform, one that would compete with Thomson Reuters’ own legal research platform, Westlaw. ROSS trained its AI model using memos that were written by a third-party company. These memos incorporated Westlaw’s copyrighted headnotes (concise statements of particular points of law in a judicial opinion). But a ROSS user would never see these headnotes, as its search engine’s output contained only the text of a judicial opinion.

In 2021, ROSS, ensnared in an expensive legal battle, shut down operations. Of course, copyright infringement is serious and startups do not have a right to infringe others’ copyrights. But was this actually copyright infringement? Or was it an overbroad, dubious assertion of copyright used to chill innovation, raise barriers to entry, limit competition in legal-information markets, and reduce public access to the law and to justice?

August Gebhard-Koenigstein (’26), an advanced student in the SLS Juelsgaard Intellectual Property & Innovation Clinic (JIPIC), working with Clinic Director Phil Malone and Supervising Attorney Nina Srejovic and with some help in the final stages from advanced student Hana Ryan, ’26, recently filed an amicus brief with the Third Circuit urging the court to find that it was the latter. The brief, submitted on behalf of six non-profit and commercial legal research technology platforms, asks the Third Circuit to reverse a Delaware district court’s 2025 summary judgment ruling in favor of Thomson Reuters’ claims. Specifically, the brief argues that (1) headnotes are not copyrightable and (2) even if they were, ROSS’s use of headnotes to train its AI model was fair use.

Copyright protects original works of authorship. Individual headnotes are by definition almost completely unoriginal—each headnote exists to faithfully, concisely, and accurately describe a singular point of law from a judicial opinion. It is therefore no surprise that many headnotes are simply copied verbatim from the judicial opinions they describe. Others, those that paraphrase a point of law rather than copy it, are simple (and often near verbatim) restatements of fact about an opinion’s content.

Consider the classic copyright case, Feist Publications, Inc. v. Rural Telephone Service Co. When discussing copyright’s originality requirement, Justice O’Connor quoted a law review article for the proposition that “the originality requirement is constitutionally mandated for all works.” Imagine you were the attorney at Westlaw tasked with summarizing this point of law in a headnote. Would there be room for you to exercise creativity? Or would doing so risk you failing to accomplish the headnote’s purpose of accurately describing a specific point of law? Here is what one of Westlaw’s attorneys came up with: “Originality, for copyright purposes, is constitutionally mandated for all works.” Westlaw, to produce a professional, functional product, is severely constrained in its creativity. Headnotes creative enough to satisfy copyright’s originality requirement would fail to do what they’re meant to do.

But even if headnotes were copyrightable, ROSS’s use was protected by the doctrine of fair use. Thanks to fair use, comedians can parody hit songs, YouTubers can review new episodes of Severance using short clips from the show, and law clinic students can include a Westlaw headnote in their blog post about a case involving copyright infringement of headnotes, all without permission from the respective copyright owners. As the Supreme Court said in Stewart v. Abend, courts apply the fair use doctrine to “avoid rigid application of the copyright statute when, on occasion, it would stifle the very creativity which that law is designed to foster.”

ROSS’s use of Westlaw’s headnotes at an intermediate stage to train its model is such an occasion. ROSS’s use was transformative—ROSS used the headnotes as an input and literally transformed that input into something entirely different – better search capability – that did not incorporate any of the copyrighted material. Moreover, ROSS is entitled greater leeway in its claim of fair use because, on a spectrum from most to least creative, headnotes land on the latter side. And lastly, ROSS’s use serves a different purpose (training an AI tool that indexes relevant cases in responses to user search queries) than Westlaw’s headnotes (summarizing a specific point of law) and thus is not a market substitute for them.

There are also clear policy reasons favoring a finding of fair use here. Free Law Project, one of the brief’s amici, runs the free online legal database and research platform, CourtListener.com, among other initiatives to make access to law more equitable and affordable. It succinctly described these policy considerations in its own blog post about the amicus brief:  “Overbroad copyright claims hurt the public. If copyright is stretched this far, it will block new companies, nonprofit organizations, and innovators from building better tools to access the law. That would make legal information more expensive and less available, especially to people who need it most.”

This lawsuit differs in some significant ways from other AI training copyright lawsuits. For example, unlike ChatGPT or Claude, ROSS’s AI tool was not “generative” (it did not write new content itself). But many of the fundamental questions are the same. And Thomson Reuters v. ROSS represents the first time a US Circuit Court will have the opportunity to directly weigh in on whether training an AI model on copyrighted material constitutes fair use. JIPIC’s amicus brief underscores the need for the Third Circuit to ensure that copyright does not exceed its legitimate scope and thereby impermissibly restrain competition, limit innovation, and harm consumers.

Image by Phil Malone

You can read the Clinic’s amicus brief here.