Two authors are suing the artificial intelligence laboratory OpenAI, claiming that it used their books without permission to train its chatbot ChatGPT, Reuters reports.

The lawsuit was brought by novelists Mona Awad (13 Ways of Looking at a Fat Girl, All’s Well) and Paul Tremblay (The Cabin at the End of the World, Survivor Song) and filed in a federal court in San Francisco.

In the lawsuit, the attorneys representing Awad and Tremblay write, “[W]hen ChatGPT is prompted, ChatGPT generates summaries of Plaintiffs’ copyrighted works—something only possible if ChatGPT was trained on Plaintiffs’ copyrighted works. Defendants, by and through the use of ChatGPT, benefit [commercially] and profit richly from the use of Plaintiffs’ and Class members’ copyrighted materials.”

The writers’ lawyers claim that their books “were copied by OpenAI without consent, without credit, and without compensation.”

The lawsuit says that OpenAI engaged in direct and vicarious copyright infringement, unfair competition, negligence, and unjust enrichment. The attorneys are asking that the suit proceed as a class action and are seeking monetary damages and injunctive relief.

OpenAI is at the center of other lawsuits. Last month, a law firm initiated a class action suit against the company, accusing it of “data scraping” blog posts and other online material. And a Georgia radio host is suing OpenAI for alleged defamation, claiming that ChatGPT-generated text stated that he embezzled money from a nonprofit organization.

Michael Schaub, a journalist and regular contributor to NPR, lives near Austin, Texas.