In his June ruling, Judge Alsup agreed with Anthropic’s argument, stating the company’s use of books by the plaintiffs to train their AI model was acceptable.

“The training use was a fair use,” he wrote. “The use of the books at issue to train Claude and its precursors was exceedingly transformative.”

However, the judge ruled that Anthropic’s use of millions of pirated books to build its models – books that websites such as Library Genesis (LibGen) and Pirate Library Mirror (PiLiMi) copied without getting the authors’ consent or giving them compensation – was not.

Pirating isn’t but training on copyrighted works is fair use, you just have to buy them.