Elon Musk announced his new company xAI and said it has the goal of understanding the nature of the universe.
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Elon Musk’s xAI has lost its second co-founder in the past two days.
Influential researcher Jimmy Barr announced his resignation in a post about X on Tuesday, thanking Musk and writing, “Thank you for helping co-found the company in its early days.”
Barr’s departure comes a day after fellow co-founder Tony Wu announced his departure from xAI, which merged with Musk’s aerospace company SpaceX earlier this month. The exodus of the xAI co-founder comes as SpaceX prepares to go public later this year.
Ba, a professor at the University of Toronto, was recognized for important research that influenced the company’s Grok version 4 AI model. In addition to Barr and Wu, other co-founders also exited Musk’s artificial intelligence venture, including Igor Babushkin, Kyle Kosik and Christian Szegedy. Greg Yang announced last month that he was stepping down from his role to focus on fighting Lyme disease.
The record all-stock deal valued SpaceX at $1 trillion and xAI at $250 billion, according to documents seen by CNBC. Musk previously used xAI to acquire his social network X (formerly Twitter) in a separate all-stock deal announced in March 2025.
The withdrawal also comes as xAI faces regulatory investigations in multiple jurisdictions in Europe, Asia, and the United States.
The investigation began after the company’s Grok AI chatbot and image generator allowed the mass creation and distribution of non-consensual, explicit images, colloquially known as deepfake pornography. Images are based on photos of real people, including children.
Musk launched xAI in 2023 with 11 others to take on OpenAI and Google. The company’s stated goal was to “understand the true nature of the universe,” according to its website at the time.
The company did not respond to requests for comment.
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