OpenAI co-founder Ilya Sutskever says he will leave the startup

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OpenAI co-founder Ilya Sutskever said Tuesday that he's leaving the Microsoft-backed startup.

"I am excited for what comes next — a project that is very personally meaningful to me about which I will share details in due time," Sutskever wrote in an X post on Tuesday.

The departure comes months after OpenAI went through a leadership crisis involving co-founder and CEO Sam Altman.

In November, OpenAI's board said in a statement that Altman had not been "consistently candid in his communications with the board." The issue quickly came to look more complex. The Wall Street Journal and other media outlets reported that Sutskever trained his focus on ensuring that artificial intelligence would not harm humans, while others, including Altman, were instead more eager to push ahead with delivering new technology.

Almost all of OpenAI's employees signed an open letter saying they would leave in response to the board's action. Days later, Altman was back at the company, and board members Helen Toner, Tasha McCauley and Sutskever, who had voted to oust Altman, were out. Adam D'Angelo, who had also voted to push out Altman, stayed on the board.

When Altman was asked about Sutskever's status on a Zoom call with reporters at the time, he said there were no updates to share. "I love Ilya. ... I hope we work together for the rest of our careers, my career, whatever," Altman said. "Nothing to announce today."

On Tuesday, Altman shared his thoughts on Sutskever's departure.

"This is very sad to me; Ilya is easily one of the greatest minds of our generation, a guiding light of our field, and a dear friend," Altman wrote on X. "His brilliance and vision are well known; his