Two senior co-founders of Elon Musk’s artificial intelligence company xAI have resigned within 24 hours, increasing exits that have now cut the firm’s founding team in half.
Yuhuai (Tony) Wu announced late on Monday night that he was leaving the company. “It’s time for my next chapter,” Wu wrote in a post on X.
“It is an era with full possibilities: a small team armed with AIs can move mountains and redefine what’s possible.”
Less than 24 hours later, Jimmy Ba followed. In his own post on Tuesday afternoon, Ba thanked Musk and said he would remain close to the company.
“Enormous thanks to @elonmusk for bringing us together on this incredible journey. So proud of what the xAI team has done and will continue to stay close as a friend of the team,” the post read in part.
Neither Wu nor Ba explained their reasons for leaving or outlined their next steps. Both departures were publicly cordial. Ba, who reported directly to Musk, did not respond to a request for comment sent via X messaging.
The exits mean six of xAI’s original 12 co-founders have now left the company since 2024. Infrastructure lead Kyle Kosic departed for OpenAI in mid-2024.
He was followed by former Google researcher Christian Szegedy in February 2025. Igor Babuschkin left in August to start a venture firm, while Greg Yang, previously at Microsoft, stepped down last month due to health reasons.
The Financial Times reported that Ba’s resignation followed challenges within xAI’s technical team over demands to improve the performance of its Grok chatbot, as Musk pushes to close the gap with competitors such as OpenAI and Anthropic.
We were unable to independently confirm those internal discussions.
The co-founders’ departures come days after SpaceX announced it would acquire xAI in a deal that values the combined company at $1.25 trillion, with plans to list later this year.
The transaction is part of Musk’s goal to expand computing capacity, including proposals to place data centres in orbit to support future workloads.
xAI’s flagship product, Grok, has faced complaints in recent months for erratic behaviour and signs of internal tampering.
Separate changes to the company’s image-generation tools also led to a surge in deepfake pornography on the platform, triggering legal and regulatory attention.
