A group of 11 nonfiction authors have joined a lawsuit in Manhattan federal court that accuses OpenAI and Microsoft of misusing books the authors have written to train the models behind OpenAI’s popular chatbot ChatGPT and other artificial intelligence-based software.

The writers, including Pulitzer Prize winners Taylor Branch, Stacy Schiff and Kai Bird — who co-wrote the J. Robert Oppenheimer biography “American Prometheus” that was adapted into the hit film “Oppenheimer” this year — told the court on Tuesday that the companies infringed their copyrights by using their work to train OpenAI’s GPT large language models.

Representatives for OpenAI, Microsoft and the authors did not immediately respond to requests for comment.

Writer and Hollywood Reporter editor Julian Sancton first filed the proposed class-action lawsuit in November. The case is one of several that have been brought by groups of copyright owners including authors John Grisham, George R.R. Martin and Jonathan Franzen against OpenAI and other tech companies over the alleged misuse of their work in AI training.

The companies have denied the allegations.

Sancton’s was the first author lawsuit against OpenAI to also name Microsoft as a defendant. The tech giant has invested billions of dollars in the artificial intelligence startup and integrated OpenAI’s systems into its products.

The amended complaint filed on Monday said that OpenAI “scraped” the authors’ works along with reams of other copyrighted material from the Internet without permission to teach its GPT models how to respond to human text prompts.

The lawsuit also said that Microsoft has been “deeply involved” in training and developing the models and is also liable for copyright infringement.

The authors asked the court for an unspecified amount of monetary damages and an order for the companies to stop infringing their copyrights.