Barret Zoph is back from OpenAI after only five months

Five months after returning to OpenAI, Barret Zoph – the company’s chief AI vendor – has left, Seaside he has learned.

Zoph returned to OpenAI in mid-January after serving as co-founder and CTO of Thinking Machines Lab, a competitive AI startup founded by OpenAI CTO Mira Murati. As soon as Zoph returned to OpenAI, the company said it would lead its business – a major step in OpenAI, as it had promised in recent months stop chasing so-called “lateral inquiries” and focus on key investment drivers such as businesses and coding ahead of the planned IPO.

OpenAI has been verified Seaside that Zofi will leave. He wrote a farewell message in the company’s Slack channel. Zoph did not immediately respond to a request for comment.

Zoph originally left OpenAI in late 2024 for Murati’s Thinking Machines Lab, but left the project abruptly in January 2026 after reports of misconceived including an unknown relationship with a partner. Say has been sent on X in January that Thinking Machines Lab had “parted ways” with Zoph and that he would be replaced as CTO.

Thinking Machines Lab has its share of problems with OpenAI. Murati took over the role of CEO from OpenAI CEO Sam Altman when he was fired in November 2023, and in the latest OpenAI lawsuit, Murati. he testified that he couldn’t believe everything Altman said. In September 2024, when Murati left OpenAI to start Thinking Machines Lab, the OpenAI staff soon followed. But three of them – including Zoph – all returned to OpenAI together last January. Fidji Simo, CEO of OpenAI for Applications, he wrote on X at the time he was “excited to welcome Barret Zoph, Luke Metz, and Sam Schoenholz back” and that the decision “had been in place for several weeks.”