OpenAI has confirmed the return of three AI researchers from Thinking Machines Lab. Barret Zoph and Luke Metz, both co-founders at the startup, will rejoin OpenAI. Sam Schoenholz, a researcher associated with the lab, will also return to the company.
Fidji Simo, OpenAI’s CEO of applications, shared the update on X. She noted the move had taken shape over several weeks. The announcement signaled a direct talent shift between OpenAI and one of the best-funded new AI labs.
Mira Murati, CEO of Thinking Machines Lab and former OpenAI chief technology officer, announced a leadership change at her company. She said the startup has parted ways with Barret Zoph. Murati also named Soumith Chintala as the new chief technology officer.
Chintala is known for long-term work in AI engineering and open-source tooling. He has contributed to major machine learning infrastructure used across the industry. Thinking Machines Lab said his appointment supports the company’s technical leadership as it continues building its research and product roadmap.
Thinking Machines Lab launched less than a year ago with Murati, Zoph, and Metz as co-founders. Murati served as OpenAI’s CTO until September 2024. After leaving, she helped form the new company with a team drawn from top AI labs.
The startup raised a $2 billion seed round in July 2025. The round included Andreessen Horowitz as lead investor and participation from Accel, Nvidia, AMD, and Jane Street, among others. Public disclosures around the financing placed the startup’s valuation at about $12 billion at the time.
Senior AI researchers often move between established labs and new ventures. Even so, the return of two co-founders to OpenAI stands out because it happened soon after the startup’s formation. One of those roles included the chief technology officer position, which typically anchors engineering execution.
OpenAI gains experienced technical leadership with Zoph and Metz, plus additional research depth with Schoenholz. Thinking Machines Lab keeps Murati as CEO and shifts the CTO role to Chintala. The market will track whether more staffing changes follow and how each organization aligns teams to near-term priorities.