Alsup ruled in June that Anthropic made fair use of the authors’ work to train

But, Kadrey v. Meta Platforms, Inc. (Judge Chhabria, June 25, 2025) states that “in most cases,” training LLMs on copyrighted works without permission is likely infringing and not fair use and "this ruling does not stand for the proposition that [...] use of copyrighted materials to train its language models is lawful."

The courts are divided, but the copyright office is not.