Former OpenAI executive Mira Murati’s startup Thinking Machines Lab is saying goodbye to two of its co-founders, both of whom are returning to OpenAI. Another former OpenAI employee who went to work for Murati’s startup is also returning to the company.
On social media on Wednesday, Murati announced the departure of Barret Zoph, the company’s co-founder and CTO. “We parted ways with Barrett,” Muratti said in a post on X. “Soumith Chintala will be the new CTO of Thinking Machines. He is a brilliant and experienced leader who has made significant contributions to the field of artificial intelligence for over a decade and is a significant contributor to our team. We could not be more excited to have him take on this new responsibility.”
Murati’s announcement made no mention of other departures.
Just 58 minutes after Murati announced Zoph’s departure, Fidji Simo, OpenAI’s CEO of Applications, announced that Zoph would be returning to OpenAI. “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 in X.
Mets is another co-founder of Thinking Machines and before worked for OpenAI for a number of years in the technical staff of the company. So does Schoenholz, whose LinkedIn profile still lists him as an employee of Thinking Machines.
Zoph previously worked for OpenAI as vice president of research, and before that, worked for six years at Google as a researcher. Murati, who served as CTO of OpenAI until September 2024; left the company and co-founded Thinking Machines with Zoph and Metz. The startup, where Murati serves as CEO, has raised significant financial backing since then, closing a $2 billion round last July with participation from Andreessen Horowitz, who led the round, as well as Accel, Nvidia, AMD and Jane Street, among others. The round valued the company at $12 billion.
TechCrunch has reached out to both Thinking Machines and OpenAI for comment. Wired reports that the split between Zoph and Thinking Labs she was not friendly. Certainly, it’s telling that Murati didn’t write more in her public message about his departure from the company.
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While talent moves between AI giants are common in Silicon Valley, the departure of co-founders from a startup less than a year after its founding is particularly notable. Losing two co-founders at the same time — especially when one was serving as CTO — could be seen as a particularly significant setback for Thinking Machines, which had assembled a high-profile group of former OpenAI, Meta, and Mistral AI researchers.
The company has also lost other key executives, including co-founder Andrew Tulloch, who left to join Meta in October. OpenAI itself has seen several co-founders depart to start or join competing ventures, including John Schulman, who left for Anthropic in August 2024 before joining Thinking Machines as Chief Scientist at its launch in February of last year.
