A 10th cofounder is leaving xAI. Elon Musk has just one more left.

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Impact Link Save Saved Read in app This story is available exclusively to Business Insider subscribers. Become an Insider and start reading now. Have an account? Log in. Another xAI cofounder, Manuel Kroiss, has told people he is leaving Elon Musk's company. Just one cofounder out of 11 remains besides Musk. The company has been in flux ahead of a widely anticipated IPO at SpaceX, which recently acquired xAI. AI-generated summary Summaries are generated by an AI model trained on Business Insider's articles. AI may make mistakes or provide inaccurate/incomplete information. We're unable to load that answer right now. Please try again. Why are xAI cofounders leaving? How does Musk plan to rebuild xAI? What challenges has xAI faced recently? What is xAI's IPO impact on SpaceX? Who is Ross Nordeen at xAI? And then there was one. Loading audio narration... XAI cofounder Manuel Kroiss has told people he is leaving the company, according to insiders with knowledge of his exit.Kroiss, who is also known as "Makro," is one of 11 engineers who helped launch the company alongside Elon Musk in 2023. With his exit, the number of cofounder departures now sits at 10. Guodong Zhang, Zihang Dai, Toby Pohlen, Jimmy Ba, Tony Wu, and Greg Yang have all stepped away since January.XAI and Kroiss did not immediately respond to requests for comment. Kroiss led pretraining, which helps train the company's AI models on large datasets, and reported directly to Musk. He also worked on improving xAI's coding models alongside Zhang, who left earlier in March. Musk said at the Abundance Summit earlier this month that xAI is "behind in coding," but the company is working to "exceed our competitors on coding."Before joining xAI, Kroiss worked at Google and DeepMind. Ross Nordeen, who came to xAI from Tesla, is the only remaining cofounder aside from Musk.The company's organizational structure has been in flux over the past few weeks, according to people with knowledge of the changes. Musk has taken over managing dozens of direct reports and has brought in workers from Tesla and SpaceX. It has also shed dozens of employees, the people said. Earlier this month, Musk said on X that "xAI was not built right first time around, so is being rebuilt from the foundations up."He has also said that the company is resifting through old xAI candidates to bring in new people. "Many talented people over the past few years were declined an offer or even an interview @xAI," Musk wrote on X.Musk's rocket company, SpaceX, acquired xAI earlier this year. The company is expected to file an initial public offering this year, which could value it at $1.5 trillion. Do you work for xAI or have a tip? Contact this reporter via email at gkay@businessinsider.com or Signal at 248-894-6012. Use a personal email address, a nonwork device, and nonwork WiFi; here's our guide to sharing information securely.