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AnthropicAnthropic trained Claude on over 7 million pirated books from LibGen and Pirate Library Mirror

A class action lawsuit (Bartz v. Anthropic) filed in August 2024 alleged Anthropic used over 7 million digital copies of copyrighted books acquired from pirating sites Library Genesis and Pirate Library Mirror to train its Claude language models. In June 2025, Judge Alsup ruled that while using legally acquired books for AI training was fair use, training on pirated copies was not protected.

Scoring Impact

TopicDirectionRelevanceContribution
Intellectual Property Ethics-againstprimary-1.00
Overall incident score =-0.885

Score = avg(topic contributions) × significance (high ×1.5) × confidence (0.59)

Evidence (1 signal)

Confirms Legal Action Aug 1, 2024 verified

Class action alleged Anthropic used 7 million pirated books from LibGen and PiLiMi to train Claude

The Bartz v. Anthropic class action filed in August 2024 alleged Anthropic used over 7 million digital copies of copyrighted books acquired from pirating sites Library Genesis and Pirate Library Mirror to train its Claude language models. In June 2025, Judge Alsup ruled piracy-based training was not fair use.

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