The talent wars in AI just dealt Mira Murati's startup a significant blow. Thinking Machines Lab is losing two co-founders, Barret Zoph and Luke Metz, who are headed back to OpenAI in a move that highlights the competitive pressure facing well-funded AI startups. The departures come less than a year after the company's $2 billion seed round valuation and underscore how difficult it is to hold onto top talent in the race to build advanced AI systems.
The exodus was announced in staggered fashion on Wednesday. Mira Murati, Thinking Machines Lab's CEO and a former CTO of OpenAI, first revealed the split in an X post, saying the company had "parted ways" with Barret Zoph. "Soumith Chintala will be the new CTO of Thinking Machines," she wrote. "He is a brilliant and seasoned leader who has made important contributions to the AI field for over a decade."
What Murati's announcement didn't mention was that the departures extended beyond Zoph. Just 58 minutes after her post, Fidji Simo, OpenAI's CEO of applications, dropped the full details on X: Zoph, Luke Metz, and Sam Schoenholz were all heading back to OpenAI. "This has been in the works for several weeks," Simo wrote, "and we're thrilled to have them join the team."
The coordinated timing raises questions about what really happened behind the scenes. According to Simo's account, the moves weren't sudden or emotional departures. They'd been in planning for weeks, which means Murati and Thinking Machines' leadership knew these departures were coming. That makes the staggered announcement strategy somewhat puzzling - Murati acknowledged Zoph's departure while remaining silent about Metz and Schoenholz, only for OpenAI to fill in the gaps minutes later.
Zoph brings serious AI credentials to OpenAI. He previously served as VP of research there and spent six years at Google as a research scientist. Metz, who co-founded Thinking Machines alongside Murati and Zoph, had spent years on OpenAI's technical staff. Schoenholz, whose LinkedIn profile still listed Thinking Machines as his current employer, had also come from OpenAI.
This is the second significant blow to Thinking Machines Lab in recent months. Co-founder Andrew Tulloch departed for Meta back in October, marking another loss of a founding-team member. While recruiting movements between AI companies are normal in Silicon Valley, losing two co-founders simultaneously - especially when one serves as CTO - signals deeper challenges at the startup.