Encyclopedia Britannica and its subsidiary Merriam-Webster have sued OpenAI, alleging copyright infringement for using their content to train AI models like ChatGPT without permission, as well as trademark infringement from the AI falsely attributing hallucinations to Britannica. The suit claims ChatGPT reproduces verbatim or near-verbatim portions, summaries, or abridgments of their works, cannibalizing traffic to their sites.
Encyclopedia Britannica, which owns Merriam-Webster, accuses OpenAI of illegally incorporating its copyrighted articles into training data for large language models, including ChatGPT, on a massive scale. ChatGPT responses reportedly include full or partial verbatim reproductions, summaries, or abridgments of Britannica's material, reducing traffic to its site. The lawsuit also claims trademark infringement, as ChatGPT generates invented content ('hallucinations') and wrongly attributes it to Encyclopedia Britannica. Britannica seeks a court injunction to halt these practices but does not specify monetary damages. This follows Britannica's unresolved lawsuit against Perplexity last year on similar grounds. Meanwhile, Anthropic and Meta successfully defended against similar suits last year by invoking fair use. OpenAI faces other litigation, including from The New York Times and Ziff Davis (parent of CNET), which sued in 2025 over AI training copyright issues. An OpenAI spokesperson stated: 'Our models empower innovation, and are trained on publicly available data and grounded in fair use.' Britannica did not immediately comment. The lawsuit was first reported on March 16, 2026.
