Britannica, Merriam-Webster sue AI answer engine Perplexity over copyright

Britannica Group, the company behind the 250-year-old Encyclopedia Britannica and Merriam-Webster, has filed a lawsuit against the AI web search startup Perplexity AI, accusing it of copyright infringement.

On September 10th, the group filed a lawsuit in New York federal court, saying that Perplexity’s answer engine systematically scrapes its websites, unlawfully copies articles, and drives traffic away.

The filing also accuses Perplexity of trademark infringement, arguing that it has linked the Britannica and Merriam-Webster names to its inaccurate AI-generated results.

“AI-created content confuses and deceives Perplexity users into believing (falsely) that the hallucinations are associated with, sponsored by, or approved by Britannica,” the filing said.

The lawsuit seeks unspecified damages, as well as requesting that Perplexity cease to misuse the content.

"When I read today’s news on Encyclopedia Britannica’s lawsuit against Perplexity, I couldn’t help but think of the challenges faced by every digital publisher in the age of AI crawlers. Publishers have always invested heavily in creating valuable, proprietary content,” Aurelie Guerrieri, Chief Marketing & Partnership Officer at DataDome, shared with Cybernews.

“Now, as AI-generated traffic surges – quadrupling in 2025 alone across DataDome’s customer base – protecting that investment has never been more challenging.”

The case is part of a string of legal challenges that Perplexity has been facing. Earlier in June, the BBC threatened legal action against the company for using BBC content to train its "default AI model". Several other organizations, including Forbes and Wired, accused Perplexity of plagiarism.

In October, News Corp, parent company of The Wall Street Journal and the New York Post, sued Perplexity for copyright infringement. Around the same time, The New York Times also sent Perplexity a “cease and desist” notice.

"Publishers need solutions that finely understand AI traffic, analyzing behavioral context, endpoint sensitivity, and traffic patterns so they can route it effectively and monetize their digital assets," added Guerrieri.

Recently, a report by Cloudflare discovered that Perplexity’s bots ignore – or sometimes don’t even fetch – robots.txt files. These files instruct web crawlers what they can or can’t access.