The Encyclopedia Fights Back

In a lawsuit that encapsulates the existential tension between AI companies and the publishers they trained on, Encyclopedia Britannica and Merriam-Webster filed suit against OpenAI on March 13, 2026 in a New York federal court. The complaint alleges "massive copyright infringement" — and the irony is hard to miss: the company that once defined authoritative knowledge is suing the company whose product has replaced it as the first stop for millions of queries.

Britannica, which owns Merriam-Webster, retains copyright over nearly 100,000 online articles. The lawsuit alleges OpenAI scraped that content to train its large language models without permission, license, or compensation.

Three Legal Theories, One Core Grievance

The complaint targets OpenAI on multiple grounds:

• Training data infringement — using Britannica's copyrighted articles to teach ChatGPT without authorization
• Output infringement — ChatGPT generating responses that contain "full or partial verbatim reproductions" of Britannica content
• RAG workflow infringement — OpenAI using Britannica articles in ChatGPT's Retrieval Augmented Generation pipeline to fetch and incorporate current information
• Lanham Act violation — AI hallucinations that falsely attribute made-up content to Britannica, damaging its trademark and reputation

"ChatGPT starves web publishers like [Britannica] of revenue by generating responses to users' queries that substitute, and directly compete with, the content from publishers like [Britannica]," the lawsuit reads.

The publishers are seeking damages, restitution of profits, and a court order blocking OpenAI from continuing the alleged conduct.

OpenAI's Defense: Fair Use

OpenAI responded with its standard fair use position. "Our models empower innovation, and are trained on publicly available data and grounded in fair use," an OpenAI spokesperson said Monday in response to the lawsuit.

That defense is increasingly being tested in court. The legal landscape around AI training data and copyright remains genuinely unsettled, with different judges reaching different conclusions. In one significant precedent, Anthropic successfully convinced federal judge William Alsup that using copyrighted content as training data is transformative enough to be legal — but Alsup still found that Anthropic had violated the law by illegally downloading millions of books rather than paying for access, resulting in a $1.5 billion class action settlement for affected writers.

A Growing Wave of Litigation

Britannica is joining a crowded courtroom. OpenAI is already facing lawsuits from the New York Times, Ziff Davis (owner of Mashable, CNET, IGN, PC Mag), and more than a dozen newspapers across the US and Canada, including the Chicago Tribune, the Denver Post, the Sun Sentinel, the Toronto Star, and the Canadian Broadcasting Corporation.

A separate Britannica lawsuit against Perplexity over similar allegations is still pending.

Why This Case Matters

The Britannica lawsuit crystallizes a question the AI industry has been hoping to avoid: what happens when AI systems don't just learn from content, but actively replace it? Publishers argue that ChatGPT's AI-generated summaries don't just compete with their content — they cannibalize the traffic that funds their operations, creating a free-rider problem at civilizational scale.

For Britannica specifically, the stakes are symbolic as much as financial. Founded in 1768 in Edinburgh, Scotland, the company was humanity's most trusted reference for over two centuries before pivoting entirely to digital in 2012. To now watch an AI system — trained on its own words — replace it in the public consciousness is the kind of disruption that demands a legal response, whatever the outcome.

"The hallucinations jeopardize the public's continued access to high-quality and trustworthy online information," the lawsuit states — a charge that cuts to the heart of what Britannica has always represented.

The case will be closely watched across the media industry as a potential bellwether for whether AI companies must pay for the information that made them possible.