Authors sue Microsoft and Anthropic over AI training on copyrighted books
Authors sued Microsoft and Anthropic for allegedly using copyrighted books without permission to train AI models. A federal judge ruled that Anthropic's use was fair use under copyright law, but found the company had improperly sourced and stored the books from piracy websites, requiring a further proceeding on damages.
What happened
Authors filed a lawsuit against Microsoft in federal court in New York alleging that the company trained its Megatron AI model on a pirated collection of 200,000 books without permission.
In a separate case, authors Andrea Bartz, Charles Graeber and Kirk Wallace Johnson sued Anthropic, claiming the company used their copyrighted works to train its Claude AI model without authorization, allegedly sourcing books largely from piracy websites.
Reported impact
The authors claim that Megatron became able to imitate their writing styles as a result of training on the pirated books.
The authors seek an injunction against the companies' infringing activities and damages of up to $150,000 per work.
Index analysis
A federal judge in California ruled in June 2025 that Anthropic's use of copyrighted books to train Claude constituted fair use under US copyright law, finding the system's use was 'distinctly transformative' in creating new original content.
However, the same judge found that Anthropic obtained the books largely from piracy websites and stored them without permission, even though they were not ultimately used for model training, requiring a separate proceeding to determine damages.
Governance controls
The companies argue that using copyrighted content to create new works is permissible and that requiring payment for all copyrighted content used would hinder industry development.
Similar lawsuits are underway against Meta, OpenAI and other AI companies over use of copyrighted material in training.
Classification
Sources and evidence
Sources not yet published
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