Encyclopedia Britannica and Merriam-Webster have filed a lawsuit against OpenAI, alleging massive copyright infringement involving nearly 100,000 online articles used to train LLMs without permission. The suit also claims OpenAI violates copyright when ChatGPT outputs verbatim reproductions of their content and uses their articles in its RAG workflow. Additionally, Britannica alleges OpenAI violates the Lanham Act by generating hallucinations falsely attributed to the publisher. This adds to a growing list of publishers suing OpenAI, including the New York Times and Ziff Davis. A similar Britannica lawsuit against Perplexity is also pending. Legal precedent on whether LLM training constitutes copyright infringement remains unsettled, though an Anthropic case resulted in a $1.5 billion settlement over how training data was obtained.