OpenAI CEO Sam Altman could be forgiven for having a bone to pick with Ilya Sutskever. 

Sutskever, the company’s co-founder, chief scientist and former board member who grew up in Israel before moving to Canada as a teen and studying under Geoffrey Hinton at the University of Toronto, played a key role in an ultimately unsuccessful attempt to oust Altman from the top job at the ChatGPT-maker. 

In a recent podcast interview with MIT computer scientist Lex Fridman, Altman spoke as openly about Sutskever and their relationship as he has since the attempted coup. “Ilya is a credit to humanity,” Altman said, but the saga was “a crazy, very painful experience.”

The context: It’s still unclear exactly what precipitated the November boardroom drama that captivated the tech world for days. OpenAI said at the time Altman was fired for being “not consistently candid.” Sutskever reportedly led the push to oust Altman, but appeared to have a quick change of heart, posting on X that he regretted his actions the following day and joining more than 700 of OpenAI’s employees in signing an open letter calling on the board to resign.

The shakeup: Days later, Altman returned as CEO and three of the four directors involved in the decision to remove Altman—including Sutskever—stepped down. Altman returned to the board last week. 

In late November, Altman wrote in a blog post that he “harbor[s] zero ill will towards” Sutskever and the two were “discussing how he can continue his work at OpenAI.” While Sutskever’s LinkedIn profile still lists his current position as OpenAI’s chief scientist, neither he nor the company has offered any public information about his future. In the interview, Altman said he can’t speak to Sutskever’s career plans, but said, “I really hope we work together for certainly the rest of my career.”

The Q* theory: According to a report from The Information, Sutskever had spearheaded a technical breakthrough (a model called Q*, or “Q-Star”) prior to the boardroom coup. Sutskever is known for his concerns about AI risk and the breakthrough reportedly raised alarms among safety-focused staff about whether the company had sufficient safeguards in place, contributing to the decision to oust Altman. In the podcast, Altman said “we are not ready to talk about” Q*. “Ilya has not seen AGI [artificial general intelligence]. None of us have seen AGI. We’ve not built AGI,” he said.

Silly-a Sutskever: Altman said Sutskever has a silly side that few get to see, saying “it’s very sweet” when it comes out. Sutskever recently revealed that side of his personality while playing with a puppy at a dinner party, Altman said. “I was thinking, ‘Oh man, this is not the side of Ilya that the world sees the most.’”

Sutskever did not respond to requests for comment.