Tony Wu, co-founder of Elon Musk’s xAI artificial intelligence firm, announced his resignation on Tuesday.
Wu shared the news in a post on X, stating, “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’s Role and Background
Wu led reasoning development at xAI, including efforts on Grok, and reported directly to Musk. A former Google DeepMind researcher, he joined xAI at its 2023 launch alongside 11 other co-founders.
Recent Leadership Shifts
His exit marks the fourth co-founder departure in the past year, following Igor Babuschkin in August 2025, Christian Szegedy, and Greg Yang. Eight of the original 12 co-founders remain. The move comes shortly after SpaceX acquired xAI in a major deal.
Looking Ahead
Wu hinted at future plans, writing, “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 thanked the team and added to Musk, “thank you for believing in the mission and for the ride of a lifetime.”
