US Appeals Court Upholds Thomson Reuters Win in AI Training Copyright Case
A US appeals court upheld a ruling that Ross Intelligence's use of Westlaw headnotes to train its AI legal search engine was not fair use.
A US federal appeals court on Tuesday upheld a ruling in favour of information services company Thomson Reuters in its copyright dispute with former legal-research rival Ross Intelligence, in the first appellate decision on the use of copyrighted material to train artificial intelligence systems.
The Philadelphia-based Third US Circuit Court of Appeals rejected Ross's argument that its AI-powered legal search engine made fair use of content from Thomson Reuters' Westlaw platform. The court's reasoning for the decision remains sealed.
Thomson Reuters, the parent company of Reuters News, sued Ross Intelligence in 2020, accusing the legal research company of copying Westlaw's "headnotes" — short summaries of points of law drawn from court opinions. The suit alleged that Ross misused thousands of these headnotes to train a competing AI-based legal search tool.
Ross shut down its platform in 2021, citing the cost of the litigation.
A federal judge in Delaware rejected Ross's fair use defence last year, finding that the company had taken the headnotes to build a competing legal research product. "Ross took the headnotes to make it easier to develop a competing legal research tool," the judge said, concluding that the use was not transformative. Ross appealed that ruling.
The case has drawn attention because it is the first copyright dispute over AI training to reach a US appeals court. Unlike the wave of litigation involving generative AI — systems that create new content — the Thomson Reuters dispute concerns an AI tool used to identify relevant court opinions in response to user queries.
Dozens of lawsuits have been filed against technology companies by authors, news outlets, music labels and others over the unauthorised use of copyrighted works to train AI systems. Tech firms have argued that such training constitutes fair use because it transforms the material into something new, while copyright owners contend that their work is being used to produce competing content that threatens their livelihoods.