Merriam-Webster and Encyclopedia Britannica sue Perplexity

Add Merriam-Webster and Encyclopedia Britannica to the growing list of companies suing AI company Perplexity for allegedly misusing its content.

The companies behind the well-known dictionary and encyclopedia have filed suit in New York federal court, accusing Perplexity of copying their material without permission and using it in its “ answer engine .” The suit claims that the system, which is being marketed as an alternative to Google and other search engines, gives users a “free ride” on the work of the companies, accessing their content “thousands” of times. (Merriam-Webster is owned by Britannica.)

“Perplexity engages in massive copying of Plaintiffs’ and other web publishers’ protected content without authorization or remuneration,” the suit reads . “Perplexity’s output answers are designed to, and do, act as substitutes for users clicking on links and otherwise going to Plaintiffs’ own websites. … For example, when a user asked Perplexity, “How does Merriam Webster define plagiarize,” Perplexity spit back the exact definition of the term from Merriam Webster, which is identical to the definition in the print Merriam-Webster Collegiate Dictionary.”

The companies are seeking unspecified monetary damages and an order that blocks Perplexity from misusing their content.

The stakes are high. Britannica says in 2024, it saw more than one billion sessions at its britannica.com site and another 1.4 billion at other sites it owns. Perplexity’s “answer engine” does not funnel traffic to those sites, but rather summarizes them for the user.

The Britannica suit is just one of a growing number against Perplexity (which is also trying to buy TikTok ). Dow Jones (publisher of The Wall Street Journal) and the New York Post sued the AI company last October, alleging it had copied content from their publications without permission and used it in the AI search engine. Perplexity’s bid to have that suit dismissed has fallen short, with a U.S. District Court judge striking down its motion in August.

Last month, Japanese media companies Nikkei and the Asahi Shimbun also filed suit on claims similar to the Dow Jones/New York Post case. And the New York Times and BBC have both threatened legal action.