By Amira McKee
xAI co-founder Tony Wu resigned from Elon Musk's company, the fourth founding member to leave the AI startup in the last year.
Wu wrote in a X post on Tuesday that he resigned from the company behind Grok Reasoning. xAI merged with Musk's SpaceX last week, forming a $1.25 trillion company that is making its stock market debut later this year.
"It's time for my next chapter," Wu wrote. "It is an era with full possibilities: a small team armed with AIs can move mountains and redefine what's possible."
Wu's exit follows the departures of Christian Szegedy, Igor Babuschkin and Greg Yang. Kyle Kosic, another founding member, left the company in 2024.
"And to Elon @elonmusk - thank you for believing in the mission and for the ride of a lifetime," he added.
Write to Amira McKee at amira.mckee@wsj.com
(END) Dow Jones Newswires
February 10, 2026 11:17 ET (16:17 GMT)
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