Just days after Elon Musk merged his A.I. startup, xAI, with SpaceX in preparation for a widely anticipated trillion-dollar IPO later this year, two of xAI’s founding employees—Yuhuai (Tony) Wu and Jimmy Ba—announced their resignations. That means half of xAI’s founding team has now left the company barely three years after its launch. Musk framed the staff exodus as growing pains. “As a company grows, especially as quickly as xAI, the structure must evolve just like any living organism. This unfortunately required parting ways with some people. We wish them well in future endeavors,” he wrote on X yesterday (Feb. 11).
Wu and Ba’s exits appeared amicable. But lower-level employees have been more candid about internal tensions at the Musk-run startup. Several members of xAI’s technical staff have also left in recent weeks, according to their posts on X and LinkedIn.
“All A.I. labs are building the exact same thing, and it’s boring,” said Vahid Kazemi, who worked on xAI’s audio models, in a post on X. “I think there’s room for more creativity. So, I’m starting something new.”
In an interview with NBC News, Kazemi also criticized the company’s working culture, saying he regularly worked 12-hour days, including holidays and weekends.
Launched in March 2023 with a roster of industry veterans from companies like OpenAI, Google, Microsoft, and Tesla, xAI will now operate as a wholly owned subsidiary of SpaceX. The new iteration of SpaceX faces no shortage of challenges: Grok continues to face legal scrutiny, while Musk’s leadership style remains a point of contention.
Here are the co-founders and notable leaders who have left xAI so far—and where they are now.
Jimmy Ba
Jimmy Ba, who led A.I. safety at xAI, announced his exit on Feb. 10. A professor at the University of Toronto who studied under A.I. pioneer Geoffrey Hinton, Ba’s research played a key role in shaping Grok’s development.
“So proud of what the xAI team has done and will continue to stay close as a friend of the team,” Ba wrote on X. He hasn’t announced his next move, but added that “2026 is gonna be insane and likely the busiest (and most consequential) year for the future of our species.”
Despite Ba’s departure, Dan Hendrycks, executive director of the nonprofit Center for AI Safety, remains a safety advisor for xAI.
Yuhuai (Tony) Wu
Tony Wu, a former research scientist at Google and postdoctoral researcher at Stanford University, announced his departure from xAI on Feb. 9.
Wu led xAI’s reasoning team. “It’s time for my next chapter…It is an era with full possibilities: a small team armed with AIs can move mountains and redefine what’s possible,” he wrote on X.
Wu has not disclosed his next role. Co-founders Guodong Zhang and Manuel Kroiss remain at xAI and are helping lead the company’s reorganization.
Mike Liberatore
While not a founding member, Mike Liberatore joined xAI as chief financial officer in April 2025, just one month after xAI acquired X in a deal that valued the combined company at $113 billion.
Liberatore, formerly a finance executive at Airbnb and SquareTrade, left after only three months. He now works as a business finance officer at OpenAI, according to LinkedIn.
Musk replaced Liberatore with ex-Morgan Stanley banker Anthony Armstrong. Armstrong advised Musk on his Twitter (now X) acquisition in 2022 and later served as a senior advisor at the Office of Personnel Management during Musk’s controversial tenure at the Department of Government Efficiency (DOGE).
Greg Yang
Greg Yang spent nearly six years as a researcher at Microsoft before joining xAI’s founding team. He left the company in January due to health complications from Lyme disease.
“Likely I contracted Lyme a long time ago, but until I pushed myself hard building xAI and weakened my immune system, the symptoms weren’t noticeable,” Yang wrote on X. He continues to advise xAI in an informal capacity.
Igor Babuschkin
Igor Babuschkin, a former research engineer at OpenAI and Google DeepMind, was a co-founder and key engineering lead at xAI. Widely known as the primary developer behind Grok, Babuschkin left in July 2025 to start his own venture capital firm, Babuschkin Ventures, focused on A.I. research and startups.
Christian Szegedy
Christian Szegedy spent 12 years at Google before joining xAI as a founding research scientist. He left xAI in February 2025 to become chief scientist at superintelligence cloud company Morph Labs.
More than a year later, he departed that role to found mathematical A.I. startup Math Inc. in September, according to his LinkedIn.
“I left xAI in the last week of February and I am on good terms with the team. IMO, xAI has a bright future,” Szegedy wrote on X.
Other senior engineers and scientists at xAI include Yasemin Yesiltepe, Zhuoyi (Zoey) Huang and Yao Fu.
Kyle Kosic
Kyle Kosic left OpenAI in early 2023 after two years to co-found xAI, where he served as engineering infrastructure lead. He departed about a year later, in April 2024, to return to OpenAI as a technical staff member.
Kosic was the first co-founder to leave xAI and did not issue a public statement. It is unclear who now leads xAI’s engineering infrastructure, though another co-founder, Ross Nordeen, remains the company’s technical program manager after previously holding the same role at Tesla.
