AI-generated books make up 20 percent of Amazon's self-published catalog but bring in only 12 percent of sales. A new study finds that revenue per book is dropping for human-written titles too, in seven of eight genres. The findings could give copyright plaintiffs the market-harm data their cases against AI companies have been missing.

Anthropic's AI training using millions of used books raised copyright concerns. The market impact of AI-generated content is a key issue.

AI-generated books make up 20 percent of Amazon's self-published catalog but bring in only 12 percent of sales. A new study finds that revenue per book is dropping for…