Sergey Brin is back at Google, working on Gemini

Sergey Brin, holding no formal executive title at Google, has reportedly gained growing influence over Gemini by working from a converted microkitchen at Mountain View headquarters, according to Business Insider's reporting on eight current and former employees.

Following August's DeepMind leadership reshuffle (Demis Hassabis becoming Alphabet's chief scientist, Koray Kavukcuoglu taking over as SVP, Jeff Dean departing after 27 years), Brin reportedly sits alongside Kavukcuoglu and hosts visits from Sundar Pichai and a Gemini coding team.

He has influenced model sizes, release windows, AGI strategy, killed and later revived a chip project called Frozen, pushed monitoring employee coding data to train Gemini, and championed recursive self-improvement research. The piece also covers Google's competitive pressure ahead of Gemini 4, researcher departures, DeepMind's new AlphaGenome Atlas genomic database release, and former DeepMind researchers founding a fusion-control startup called Fusionality.

Questions this post answers

What happened to Jeff Dean at Google DeepMind?

Jeff Dean left Google DeepMind after 27 years to start his own company, following an August leadership reshuffle in which Demis Hassabis gave up the Google DeepMind chief executive title to become Alphabet's chief scientist, and Koray Kavukcuoglu became senior vice president of Google DeepMind. Dean previously led a chip project internally known as Frozen, which Sergey Brin reportedly cut in 2025.

What is AlphaGenome Atlas from DeepMind?

AlphaGenome Atlas is a 1-petabyte database released by DeepMind containing precomputed predictions for all 9 billion possible single-letter changes in the human genome, letting researchers rank which variants are most likely to affect a trait or disease. It is free for researchers, while commercial users like Isomorphic Labs pay a license fee; it helped identify a DNM1 variant linked to severe epilepsy in one test.

How do Google researchers get access to TPU compute for Gemini development?

Google researchers formally request TPU chip access through a process requiring sign-off from senior managers, though this route can be difficult even for the Gemini team. Some teams instead trade work with other groups in exchange for chip access, and an informal alternative is appealing directly to Sergey Brin, who has outsized influence over resource allocation despite holding no executive title.