Carreyrou v. Anthropic PBC
Issue
Whether plaintiffs asserting copyright infringement claims against multiple competing AI developers—Anthropic, Google, OpenAI, Meta, xAI, Perplexity, Apple, and Nvidia—arising from the alleged use of the same shadow-library piracy ecosystem to train large language models may be joined as defendants in a single action under Federal Rule of Civil Procedure 20(a)(2), or whether those claims must be severed into separate proceedings under Rule 21.
What Happened
Plaintiffs—professional authors and rights holders—filed an amended complaint alleging that all defendants systematically sourced copyrighted books from the same interconnected network of piracy repositories (LibGen, Z-Library, Bibliotik, Books3, The Pile) and used those works in materially similar LLM training pipelines without authorization. Multiple defendants, including Google, Anthropic, Perplexity, Meta, and xAI, filed motions to sever, arguing that their respective conduct constituted independent acts by separate competitors rather than a common transaction or occurrence. Plaintiffs filed a consolidated opposition contending that severance is impermissible under Rule 20(a)(2) because the claims share a unifying factual nucleus—a single industry-wide scheme with common sourcing, uniform technical copying steps (ingestion, preprocessing, tokenization, iterative training), and parallel commercialization—and that common legal questions predominate, including the scope of fair use for AI training, the market-harm analysis under *Campbell v. Acuff-Rose*, and the willfulness standard. Plaintiffs additionally argued that severance would prejudice them by forcing duplicative discovery and parallel expert proceedings, and requested in the alternative that any severed actions be immediately consolidated under Rule 42(a).
Why It Matters
This procedural dispute is an early but consequential test of whether mass AI copyright litigation against industry-wide defendants can proceed in a single forum, with the court's joinder ruling likely to determine whether fair use defenses—particularly the fourth-factor market-harm inquiry, which requires examining the aggregate effect of all defendants' conduct on the licensing market for AI training data—are adjudicated consistently or fragmented across parallel actions. The outcome may signal how courts will structure the wave of generative-AI copyright cases and whether the "industry-wide scheme" theory is sufficient to sustain multi-defendant joinder in AI training-data litigation.
Related Filings
Other proceedings in the same litigation tracked by this monitor.
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