Bartz v. Anthropic PBC, 3:24-cv-05417

Anthropic PBC, an AI software company, downloaded millions of copyrighted books from pirate sites and purchased millions of used print books, which it digitized for building a central library and for training large language models (LLMs) like Claude.
Plaintiffs are authors whose works were copied by Anthropic without authorization; they sued for copyright infringement, focusing on both the pirated and purchased copies used in model training and the creation of Anthropic’s internal digital library.
Anthropic's use of books involved copying full texts for two main purposes: (1) general storage/research in a central digital library; and (2) training LLMs to generate new text outputs.
Key procedural step: Anthropic moved for summary judgment on the grounds that its uses of the works at issue were protected "fair uses" under §107 of the Copyright Act, prior to class certification.
The Court analyzed different uses separately: use for model training, use as replacements for purchased print books, and uses involving retention of pirated copies in the research library.
The opinion addresses whether each distinct use—training, print-to-digital conversion, and building the library with pirated works—was fair use under the multi-factor test.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Use for LLM Training	Copying and memorizing works for LLMs is not transformative; infringes core rights.	Training is transformative, akin to human learning, with no output infringement.	Exceedingly transformative use; fair use.
Print-to-Digital Conversion (Purchased)	Changing format without authorization is infringement, regardless of purchase.	Destructive scan merely replaces print with digital copy for internal use; fair	Format change was transformative for these purposes; fair use.
Retention of Pirated Library Copies	Retaining pirated works is not justified by any transformative use.	All uses (including piracy) are justified if ultimately for training LLMs.	Building/retaining pirated library is not fair use; liable.
Market Harm from LLM Training	LLM training displaces market for licensing works for AI training.	No displacement of traditional markets or outputs; Authors not entitled to restrict transformative LLM training.	LLM training did not usurp protected market; fair use.

Campbell v. Acuff-Rose Music, Inc., 510 U.S. 569 (core four-factor fair use test and transformative use analysis)
Google LLC v. Oracle Am., Inc., 593 U.S. 1 (fair use timing and burden for summary judgment)
Andy Warhol Found. for the Visual Arts, Inc. v. Goldsmith, 598 U.S. 508 (key to analyzing transformative uses and subjective intent)
Authors Guild v. Google, Inc., 804 F.3d 202 (Google Books; transformative fair use for digitizing/search use)
Sony Corp. of Am. v. Universal City Studios, Inc., 464 U.S. 417 (format-shifting and noncommercial time-shifting as fair use)
A&M Records, Inc. v. Napster, Inc., 239 F.3d 1004 (reproduction/distribution of protected works is not excused by transformative intent when acquiring copyrighted works illegally)
Harper & Row, Publishers, Inc. v. Nation Enters., 471 U.S. 539 (commercial motive as a factor; creative works core to copyright protection)