A federal judge in San Francisco has ruled that training an AI model on copyrighted works without specific permission to do so was not a violation of copyright law. U.S. District Judge William Alsup said that AI company Anthropic could assert a “fair use” defense against copyright claims for training its Claude AI models on copyrighted books.

Copyrighted books can be used to train artificial intelligence models without authors' consent, a federal judge ruled Monday — a major victory for Anthropic.