Five major publishers sued Meta Platforms in Manhattan federal court on Tuesday, alleging that the tech giant misused their books and journal articles to train its artificial intelligence models.

Elsevier, Cengage, Hachette, Macmillan and McGraw Hill, as well as author Scott Turow, alleged in the proposed class-action complaint that Meta pirated millions of their works and used them without permission to train its Llama large language models to respond to human prompts.

“Meta’s mass-scale infringement isn’t public progress, and AI will never be properly realized if tech companies prioritize pirate sites over scholarship and imagination,” Maria Pallante, the president of the Association of American Publishers, said in a statement.

Meta has denied any wrongdoing.

“AI is powering transformative innovations, productivity and creativity for individuals and companies, and courts have rightly found that training AI on copyrighted material can qualify as fair use,” a Meta spokesperson responded in a statement on Tuesday. “We will fight this lawsuit aggressively.“

The publishers allege that Meta pirated works ranging from textbooks to scientific articles to novels including The Fifth Season by NK Jemisin and The Wild Robot by Peter Brown for its AI training. They asked the court for permission to represent a larger class of copyright owners and an unspecified amount of monetary damages.

The lawsuit opens a new front in the ongoing copyright battle between creators and tech companies over AI training, in which dozens of authors, news outlets, visual artists and other plaintiffs have sued companies including Meta, OpenAI and Anthropic for infringement. All of the pending cases are likely to revolve around whether AI systems make fair use of copyrighted material by using it to create new, transformative content. The first two judges to consider the matter issued diverging rulings last year. Amazon- and Google-backed Anthropic was the first major AI company to settle one of the cases, agreeing last year to pay a group of authors $1.5bn to resolve a class-action lawsuit that could have cost the company billions more in damages for alleged piracy. The New York Times has sued OpenAI and Microsoft for copyright infringement as well.