Bankrupt crypto exchange FTX has paused the sale of its highly-coveted $500 million stake in artificial intelligence (AI) startup Anthropic, according to a report from Bloomberg.

Perella Weinberg, the investment bank handling FTX’s bankruptcy, told bidders this month about the pause, people familiar with the matter told Bloomberg. The move followed months of due diligence on the stake in the creator of ChatGPT rival chatbot Claude being done by the bidders, the people said.

FTX and sister hedge fund Alameda had invested $500 million in Anthropic, according to an internal document circulated before last November’s bankruptcy filing and seen by Bloomberg. Semafor reported in early June that FTX was looking to sell its shares for “hundreds of millions of dollars.”

In May, Anthropic raised $450 million in Series C funding led by Spark Capital with participation from Google, Salesforce Ventures, Sound Ventures, Zoom Ventures and others. According to Semafor’s early June report, Anthropic is valued at $4.6 billion.