A U.S. judge on Wednesday handed Meta a victory over authors who accused the technology giant of violating copyright law by training Llama artificial intelligence on their creations without permission.

District Court Judge Vince Chhabria in San Francisco ruled that Meta's use of the works to train its AI model was "transformative" enough to constitute "fair use" under copyright law, in the second such courtroom triumph for AI firms this week.

However, it came with a caveat that the authors could have pitched a winning argument — that by training powerful generative AI with copyrighted works, technology firms are creating a tool that could let a sea of users compete with them in the literary marketplace.