A US judge has ruled that the use of copyrighted books to train artificial intelligence (AI) software is legal under US copyright law, but the AI firm **Anthropic** must stand trial over allegations of using pirated copies.

• The ruling allows **Anthropic** to use a "fair use" defense, but the company could face up to $150,000 in damages per copyrighted work.
• Key plaintiffs include authors Andrea Bartz, Charles Graeber, and Kirk Wallace Johnson.
• Judge William Alsup noted that the transformative use of the authors' works does not infringe on their rights if no infringing copies were created.