John Schulman, co-founder of OpenAI, who departed from AI company Anthropic earlier this week after a brief tenure of just five months, is reportedly joining former OpenAI CTO Mira Murati’s secretive new startup, according to Fortune.

It is unclear what Schulman’s role will be at the new venture. Fortune was unable to obtain this information, and Murati has been tight-lipped about the venture since she left OpenAI in September. However, one source revealed to Fortune that Murati has recruited additional ex-OpenAI staff, including Christian Gibson, who had been serving on OpenAI’s supercomputing team.

Murati was reportedly in talks to raise over $100 million for her company in October.

Murati is credited as one of the leading architects of ChatGPT. Schulman left OpenAI last August for Anthropic. He posted about the decision on X, stating that it stemmed from a desire to deepen his focus on AI alignment — the science of ensuring AI behaves as intended — and engage in more hands-on technical work.