Britannica Sues OpenAI Over AI Training

Encyclopaedia Britannica and Merriam-Webster sued OpenAI in Manhattan federal court on March 14, 2026, over unauthorized use of their content.

The lawsuit accuses OpenAI of copying nearly 100,000 Britannica articles to train its GPT large language models without permission. This case adds to a growing list of copyright disputes between content creators and AI companies, raising urgent questions about where fair use ends and infringement begins

The Core Allegations

Britannica filed the complaint in Manhattan federal court on Friday, March 14, 2026. The lawsuit targets Microsoft-backed OpenAI directly.

The complaint states that OpenAI used Britannica's online articles, encyclopedia entries, and Merriam-Webster dictionary definitions to train ChatGPT. Britannica says this was done without permission or compensation.

Britannica also accuses OpenAI of producing "near-verbatim" copies of its content through ChatGPT responses. The company argues this diverts users who would otherwise visit its websites directly, cutting into its web traffic.

Trademark Claims

Beyond copyright, Britannica raises trademark infringement claims in the same lawsuit. It accuses OpenAI of implying it had permission to reproduce Britannica's material.

The complaint also states that OpenAI wrongfully cited Britannica as a source in false AI "hallucinations." Hallucinations refer to instances where AI systems generate confident but factually incorrect or fabricated information.

This dual-track legal strategy, combining copyright and trademark claims, makes the case broader than most AI training lawsuits filed so far.

What Both Sides Say

OpenAI responded to the lawsuit through a spokesperson on Monday. "Our models empower innovation, and are trained on publicly available data and grounded in fair use," the spokesperson said.

Spokespeople and attorneys for Britannica did not respond to a request for comment by Monday. The complaint itself outlines Britannica's position that OpenAI "cannibalized" its web traffic through AI-generated summaries of its content.

The fair use argument has been OpenAI's standard defense across multiple lawsuits. AI companies broadly argue that training on publicly available content transforms it into something new, which qualifies as fair use under copyright law.

Broader Legal Context

This lawsuit is not Britannica's first action against an AI company. Britannica filed a related lawsuit against AI startup Perplexity AI last year, and that case remains ongoing as of March 2026.

The OpenAI case joins a growing wave of high-stakes copyright suits brought by authors, news publishers, and now reference publishers against AI developers. These cases collectively challenge whether AI training on scraped web content is legally permissible.

Britannica is seeking an unspecified amount of monetary damages. It is also requesting a court order to block the alleged ongoing infringement by OpenAI.

About Encyclopaedia Britannica

Encyclopaedia Britannica, Inc. is a Chicago-based reference and educational publisher founded in 1768. It operates the online encyclopedia Britannica.com and owns the Merriam-Webster dictionary brand, one of the most widely used English-language dictionary resources in the United States. Britannica transitioned to a fully digital model in 2012, making web traffic and online content licensing central to its business model.