Reddit is suing artificial intelligence startup Anthropic for what it’s calling a breach of contract and for engaging in “unlawful and unfair business acts” by using the social media company’s platform and data without authority.

Reddit’s lawsuit, which was filed Wednesday, accuses the Amazon-backed AI company of breaching its user agreement. “As far back as December 2021…Anthropic was already—without authorization and in direct violation of Reddit’s User Agreement—training Claude on Reddit users” posts, the lawsuit claims.