Ilya Sutskever, one of OpenAI’s original 11 co-founders and its chief scientist, has left the company, he announced in a post from his account on X.

OpenAI confirmed the news in a blog post on its website which included a note from CEO and co-founder Sam Altman, who Sutskever last year moved to fire along with OpenAI’s old non-profit holding company’s board of directors.

OpenAI director of research Jakub Pachocki has been named the company’s new chief scientist. Read Altman’s note below:

Ilya and OpenAI are going to part ways. 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. His brilliance and vision are well known; his warmth and compassion are less well known but no less important.

OpenAI would not be what it is without him. Although he has something personally meaningful he is going to go work on, I am forever grateful for what he did here and committed to finishing the mission we started together. I am happy that for so long I got to be close to such genuinely remarkable genius, and someone so focused on getting to the best future for humanity.

Jakub is going to be our new Chief Scientist. Jakub is also easily one of the greatest minds of our generation; I am thrilled he is taking the baton here. He has run many of our most important projects, and I am very confident he will lead us to make rapid and safe progress towards our mission of ensuring that AGI benefits everyone.

In an article published by The New York Times, the 38-year-old Sutskever “added that he was starting a new project, but did not elaborate.”

While an abrupt and sudden announcement that is in many ways, poorly timed, coming on the heels of OpenAI’s announcement just yesterday of a new foundation AI model GPT-4o, and will likely cloud coverage of that, the news of Sutskever’s departure is likely not a surprise to anyone who has been paying close attention to the company over the last year.

After all, Sutskever was said to be among the ringleaders if not the ringleader of the corporate “coup” that ousted Altman in November 2023 before ultimately much of the rest of the company — including more than 500 employees — pushed to have him reinstated.

Indeed, since that time, Sutskever had not been seen publicly at any OpenAI events and inspired a meme among AI workers and influencers on X and social media, “Where’s Ilya.”

Now we now the answer: not at OpenAI, not anymore. What he does next though will surely reverberate around tech and the AI industry in a big wa.