Talent u-turn as OpenAI researchers leave Mira Murati’s AI startup

The high-stakes world of artificial intelligence (AI) has seen another shift in its talent landscape as three prominent researchers depart Mira Murati-founded Thinking Machines Lab to return to Sam Altman-led OpenAI.

This exodus includes two of the startup’s co-founders, Barret Zoph and Luke Metz, alongside staffer Sam Schoenholz.

The move comes less than a year after the company was established by Murati, the former chief technology officer of OpenAI who left the ChatGPT maker in 2024 after a tenure of six-and-a-half years.

In an internal memo to the company, she had said she was stepping away to create the time and space to do her "exploration".

The transition was made public through a series of social media updates.

Murati confirmed the exit of her second-in-command on X, stating, “We have parted ways with Barret”. 

Naming Soumith Chintala as the new CTO, she said, “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.”

Less than an hour after Murati’s post, OpenAI’s CEO of applications, Fidji Simo, confirmed the return of the trio.

Simo wrote on X, “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 swift sequence of events suggests a pre-planned transition that highlights the intense competition for technical expertise in the world of AI.

Zoph is a veteran of the industry, having previously served as the vice-president of research at OpenAI and spending six years as a research scientist at Google. His departure from Thinking Machines Lab is particularly significant given his role as a founding member. Metz also brings substantial experience from his previous tenure on the technical staff at OpenAI.

In July 2025, Thinking Machines Lab closed a $2 billion seed funding round led by Andreessen Horowitz, which included participation from NVIDIA, Accel, ServiceNow, Cisco, AMD and Jane Street. This capital injection valued the startup at $12 billion.

These departures can be viewed as a meaningful setback for Murati’s venture, which had successfully poached several researchers from Meta and Mistral AI.

This is not the first time the company has lost founding members, as Andrew Tulloch previously left to join Meta in October last year.

The revolving door of AI talent continues to spin as organisations compete for the minds capable of building the next generation of machines.