Mira Murati’s startup Thinking Machines Lab lost co-founder and CTO Barret Zoph to OpenAI on Wednesday, followed by co-founder Luke Metz and former OpenAI staffer Sam Schoenholz returning to the company.
Murati, CEO of Thinking Machines Lab, announced Zoph’s departure on X. She stated, “We have part ways with Barret.” In the same post, she introduced Soumith Chintala as the new CTO. Murati described Chintala as “a brilliant and seasoned leader who has made important contributions to the AI field for over a decade, and he’s been a major contributor to our team. We could not be more excited to have him take on this new responsibility.” Her announcement addressed only Zoph’s exit and contained no reference to other personnel changes.
We have parted ways with Barret Zoph.
Soumith Chintala will be the new CTO of Thinking Machines. He is a brilliant and seasoned leader who has made important contributions to the AI field for over a decade, and he’s been a major contributor to our team. We could not be more…
— Mira Murati (@miramurati) January 14, 2026
Exactly 58 minutes after Murati’s post, Fidji Simo, OpenAI’s CEO of applications, revealed on X that Zoph, Metz, and Schoenholz would rejoin OpenAI. Simo wrote, “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 thrilled to have them join the team.” This sequence highlighted the rapid transition of the three individuals from Thinking Machines Lab back to their former employer.
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 thrilled to have them join the team. Barret will report to me; Luke and Sam will report into Barret. More to come on what they’ll focus on soon!
— Fidji Simo (@fidjissimo) January 15, 2026
Zoph previously held the position of VP of research at OpenAI. Prior to that role, he worked for six years at Google as a research scientist. Luke Metz served as a co-founder of Thinking Machines Lab and spent several years on OpenAI’s technical staff. Sam Schoenholz, another former OpenAI employee, co-founded Thinking Machines Lab with Murati and Zoph; his LinkedIn profile at the time still indicated employment there.
Murati acted as CTO of OpenAI until September 2024, after which she departed to establish Thinking Machines Lab alongside Zoph and Metz. The startup quickly secured substantial funding. In July, it completed a $2 billion seed round led by Andreessen Horowitz. Additional investors included Accel, Nvidia, AMD, and Jane Street, among others. This investment valued Thinking Machines Lab at $12 billion.
Wired reported that the separation between Zoph and Thinking Machines Lab lacked amicability.
