Sutskever, part of the founding team at the company, was also a key player in the brief but dramatic ouster of OpenAI Chief Executive Officer Sam Altman in November. 

“After almost a decade, I have made the decision to leave OpenAI,” Sutskever wrote. “The company’s trajectory has been nothing short of miraculous.” 

Upon OpenAI’s founding 2015, Sutskever served as its research director; he was recruited to join the company by Elon Musk. Later, he was one of several board members who moved to fire Altman. But soon after, Sutskever said he regretted the decision. 

After Altman returned to the company in late November, Sutskever said in a blog post that he would not go back to his former post as a board member, but that the company was “discussing how he can continue his work at OpenAI.”

Sutskever is well known in the field of AI, dating back to his research on neural networks at the University of Toronto, and continuing at Google, where he worked at the company’s Google Brain lab.

OpenAI did not immediately return a request for comment.

In a post on X, Altman wrote, “Ilya is easily one of the greatest minds of our generation, a guiding light of our field, and a dear friend.”

On X, Sutskever posted that he is working on an as-yet-unnamed project that is “very personally meaningful” for him.

The company’s new chief scientist, Pachocki has worked at OpenAI since 2017. He had been the startup’s research director.