Former OpenAI executive Mira Murati’s startup Thinking Machines Lab is bidding farewell to its two co-founders, who will both return to OpenAI. Another former OpenAI staff member who worked for Murati’s startup also plans to return to the company.
On Wednesday, Murati announced on social media that the company’s co-founder and chief technology officer, Barrett Zoff, is leaving the company. “We have parted ways with Barrett. Somis Chintala will be the new CTO of Thinking Machines,” Murati said in a post on X. “He is an excellent and experienced leader who has made important contributions to the AI field for over a decade and is a great addition to our team. I couldn’t be more excited to have him take on this new responsibility.”
Mulaty’s announcement did not mention any other departures.
Just 58 minutes after Murati announced Zoph’s departure, OpenAI Applications CEO Fidji Simo announced that Zoph would be returning to OpenAI. “We’re excited to welcome Barret Zoph, Luke Metz, and Sam Schoenholz back to OpenAI! This has been in the works for several weeks, and we’re excited to have them join the team,” Simo wrote on X.
Metz is another co-founder of Thinking Machines and previously worked for many years on the technical staff at OpenAI. So is Schoenholz, whose LinkedIn profile still lists him as working at Thinking Machines.
Zoph previously worked as VP of Research at OpenAI and before that spent six years as a research scientist at Google. Murati, who served as OpenAI’s CTO until September 2024, left the company and co-founded Thinking Machines with Zoph and Metz. The startup, headed by Murati, has since raised significant funding and closed a $2 billion seed round last July, led by Andreessen Horowitz, with participation from Accel, Nvidia, AMD, Jane Street and others. This round valued the company at $12 billion.
TechCrunch has reached out to both Thinking Machines and OpenAI for comment. Wired reports that the breakup between Zoph and Thinking Labs was not amicable. Indeed, it is telling that Murati did not elaborate further on his departure in his official message.
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Talent transfers between AI giants are common in Silicon Valley, but it’s especially notable that a startup’s co-founders leave within a year of its founding. The simultaneous loss of two co-founders, especially one while serving as CTO, may be seen as a particularly significant setback for Thinking Machines, which had assembled a high-profile team of former OpenAI, Meta, and Mistral AI researchers.
The company also lost other key personnel, including co-founder Andrew Tulloch, who left in October to join Meta. OpenAI itself has seen many co-founders leave to start or join competing ventures, including John Schulman, who left Anthropic in August 2024 to join Thinking Machines Lab, which launched last February, as a principal scientist.
