xAI cofounder Yuhuai (Tony) Wu resigns amid founder exodus

Yuhuai (Tony) Wu, a cofounder of Elon Musk’s artificial intelligence startup xAI, said in a public post on X that he has resigned from the company and will move on to a new chapter. “I resigned from xAI today. This company - and the family we became - will stay with me forever. I will deeply miss the people, the warrooms, and all those battles we have fought together,” Wu wrote. He added that “it's time for my next chapter” and hinted at forming “a small team” that could “move mountains and redefine what's possible,” concluding with “Elon - thank you for believing in the mission and for the ride of a lifetime.”

Wu’s departure, announced in the Feb. 10–11 timeframe, is the latest in a string of senior exits from the three-year-old company. xAI was founded in March 2023 by Elon Musk and 12 founding members. Public reports and company posts indicate multiple cofounders have left or stepped back: Kyle Kosic reportedly left in June 2024; Igor Babuschkin departed in August 2025 to launch an AI safety venture capital firm; Christian Szegedy exited in 2025; Greg Yang recently stepped back citing health concerns; and Jimmy Ba confirmed his own departure less than 24 hours after Wu’s announcement, expressing gratitude for the team and pride in what it achieved.

Public accounts diverge on the precise running count of founders who have left. What is consistent is that half a dozen founders or senior engineers have publicly changed their status in recent months, and the departures have clustered around a broader corporate reorganization.

That reorganization folded xAI into SpaceX in a move framed by company leadership as enabling ambitious engineering such as orbital data centers. Musk’s public language about the plan has included talk of orbiting data centers and even “scaling to make a sentient sun to understand the Universe and extend the light of consciousness to the stars!” Observers have suggested the integration also serves a financial purpose as xAI prepares to be part of a SpaceX public filing, arguing that combining xAI’s losses with SpaceX’s profits could smooth an IPO path.

Wu did not publicly attribute his resignation to the SpaceX integration. Company leadership and Musk have not issued a public comment on his exit. External reporting has also noted product and operational tensions at xAI: the Grok chatbot drew criticism for erratic behavior and internal tampering allegations, and changes to the company’s image-generation tools were followed by reports of a surge in deepfake pornography and legal scrutiny. Those developments have been cited as potential contributors to internal friction, though no single issue has been presented publicly as the proximate cause of the recent departures.

Operationally, reported figures suggest xAI had expanded rapidly, opening a new engineering office in Washington and maintaining offices in the Bay Area and Bellevue, with data centers in Memphis. Some reporting places the company’s headcount at roughly 1,200 employees as of March 2025, including large numbers of so-called AI tutors; roughly 500 of those tutors were reportedly laid off last September.

For now, Wu signaled a pivot to smaller-scale work with AI, while leaving open the possibility of continued close ties to former colleagues. His exit will intensify scrutiny of xAI’s personnel stability and of SpaceX’s plans as both companies move toward a potential public filing.