Bartz v Anthropic
The court held that Anthropic’s use of copyrighted books to train large language models was fair use, and that converting lawfully purchased print books into private searchable digital library copies was also fair use, but denied summary judgment as to millions of pirated books retained in a general-purpose library.
What it does The order separates Anthropic’s copying into distinct uses. Training copies were highly transformative because Claude generated new text without allegedly providing users with infringing copies or knockoffs of the authors’ works. The print-to-digital conversion was independently fair because each purchased print copy was destroyed and replaced by a searchable digital copy kept internally. By contrast, downloading and retaining pirated books for a permanent, general-purpose library was not excused by later training use; the court described the piracy as a separate, nontransformative use.
Who it affects The ruling directly affects Anthropic and authors Andrea Bartz, Charles Graeber, and Kirk Wallace Johnson, together with Bartz Inc. and MJ + KJ Inc. It addresses books obtained through Books3, Library Genesis, and the Pirate Library Mirror, as well as Anthropic’s Claude services and related LLMs.
Why it matters The decision distinguishes AI training from the acquisition and retention of unauthorized source copies. It grants Anthropic summary judgment only for training and purchased-copy digitization, leaving liability and damages for the pirated library copies—including possible willfulness—to trial.
Key dates and numbers
- June 23, 2025: order dated and entered.
- August 2024: authors filed the putative class action.
- January–February 2021, June 2021, and July 2022: identified piracy acquisitions.
- More than seven million pirated book copies were downloaded and retained.