Andrew Tulloch Reportedly Leaves Meta Less Than a Year After Returning

Meta is reportedly losing AI researcher Andrew Tulloch less than a year after his return to the company, removing a high-profile recruit from the lab at the center of Mark Zuckerberg’s AI strategy. Tulloch delayed his departure until Meta launched its new open-source AI models and Muse assistant, according to Semafor.

Semafor reported that Tulloch is leaving Meta, citing a person briefed on the matter. CTech separately reported that he resigned Wednesday without giving a reason. Tulloch worked in Meta’s TBD lab, which Semafor described as a core part of Zuckerberg’s AI push and as being led by Scale AI founder Alexandr Wang. Meta and Tulloch did not respond to CTech’s requests for comment.

A short return after a long first stint

Tulloch had already spent 11 years at Meta before leaving in 2023. He then co-founded Thinking Machines Lab with former OpenAI chief technology officer Mira Murati. That background made his return notable: it brought back a researcher with both a long Meta history and a role in a newer AI lab founded by a former OpenAI executive.

A recruitment campaign meets a retention test

The reported compensation was part of Meta’s aggressive effort to recruit elite AI talent. CTech said Meta had first tried to acquire Thinking Machines Lab, an approach Murati rejected, before Zuckerberg reportedly pursued more than a dozen of its engineers, including Tulloch. The reported offer drew particular attention because of its potential size.

What the recruitment record shows

• Meta reportedly pursued a purchase of Thinking Machines Lab before seeking to recruit its engineers directly.
• Tulloch initially declined Meta’s reported compensation offer before later joining the company.
• His tenure after returning lasted less than a year, according to CTech.

The unanswered part of the exit

Neither report establishes why Tulloch chose to leave or where he may work next. That limits what can be inferred from the departure: it does not, on its own, explain Meta’s ability to retain researchers or Tulloch’s view of the company’s AI work. But his exit arrives while Meta is competing with OpenAI, Anthropic and Google, where a small group of experienced researchers remains highly sought after.

For Meta, the immediate change is simpler than the wider interpretation: a researcher it had worked hard to bring back is now departing after the launch he reportedly stayed to complete. Whether that becomes a one-off personnel change or another move in the competition for AI talent will depend on what Tulloch does next and how Meta fills the role.