Demis Hassabis steps back from day-to-day Google DeepMind leadership; Jeff Dean departs after 27 years

Google is reshuffling the top of its AI organization: DeepMind CEO Demis Hassabis is moving into a Chair and Chief Scientist role, and longtime chief scientist Jeff Dean is leaving the company after nearly three decades to start an independent research venture.

What's new

In a joint message published to Google's blog, CEO Sundar Pichai and Hassabis laid out the changes. "Demis will become the Chair of GDM and Chief Scientist of Alphabet, while continuing to lead Isomorphic Labs," the post states. Hassabis explained his own reasoning for the shift: "now is the right time for me to hand over my day-to-day operational responsibilities at GDM, so that I have the time and space to focus on the big picture."

Taking over Hassabis's operational duties is Koray Kavukcuoglu, currently GDM's Chief Technology Officer and Chief AI Architect. Per the post, "Koray, the current Chief Technology Officer of GDM and our Chief AI Architect, will step up as SVP of Google DeepMind, reporting to me" — overseeing Gemini model development, frontier AI research, and the Gemini app and developer teams.

Separately, the post confirms that Jeff Dean and Google Senior Fellow Sanjay Ghemawat are leaving: "Jeff and Google Senior Fellow Sanjay Ghemawat are launching an independent public benefit corporation to accelerate discoveries in ML, science, and engineering." Dean has been at Google for 27 years and has been one of the architects of its computing and AI infrastructure, from early distributed-systems work to leading AI development in recent years.

The post also folds in current momentum numbers: the Gemini app has "reached 950M+ monthly users" and Gemma models have "surpassed 900M+ downloads," with Pichai noting Flash is in high demand and the company's Cyber model is live.

Context

Hassabis co-founded DeepMind in 2010 and has run Google's combined AI research organization since Google Brain and DeepMind were merged into Google DeepMind in 2023. He has increasingly split his attention toward Isomorphic Labs, the Alphabet-backed drug-discovery company he also leads, and toward AGI-focused strategy. Dean, meanwhile, has been one of Google's most senior technical leaders since 1999, shaping systems like MapReduce, TensorFlow, and the company's large-scale AI infrastructure, and more recently serving as Google's chief scientist.

Why it matters

This is a structural change at the top of one of the world's most influential AI labs, not a routine reshuffle. Hassabis stepping back from day-to-day operations — while retaining the Chief Scientist title and his Isomorphic Labs role — signals Alphabet wants its highest-profile AI leader focused on long-horizon AGI strategy and health applications rather than running GDM's daily operations. Handing that operational authority to Kavukcuoglu consolidates control of Gemini development and frontier research under a single deputy who has been Hassabis's longtime technical lieutenant. Dean's departure after 27 years removes one of Google's most tenured technical leaders from the company at a moment when competition for elite AI research talent is intense; that he is founding a new outfit focused on automating scientific discovery — with Google itself reportedly involved as an investor — suggests the split is being managed as a continued alliance rather than a clean break.