The complaints allege Meta Platforms Inc. operated a book-scanning program called Project Vellum starting around mid-2025 that purchased and scanned physical books to train its Muse Spark and Muse Glimmer AI models.

Large language models (LLMs) are advanced AI systems trained on massive text datasets to understand, generate, and reason about human language, powering applications such as chatbots, code generation, summarization, and scientific discovery.