Google DeepMind's Hassabis becomes Chair, Jeff Dean exits to start Discovery Loop

Google DeepMind is undergoing a sweeping leadership reshuffle that separates its two most iconic figures. Demis Hassabis, co-founder and CEO of Google DeepMind, is stepping up to become Chair of Google DeepMind and Chief Scientist of Alphabet, while continuing to lead Isomorphic Labs. CEO Sundar Pichai framed the move positively on X, saying Hassabis is "stepping up, not down." Meanwhile, Jeff Dean — Google's employee #30 and a 27-year veteran who helped build core Search infrastructure and co-founded Google Brain — is leaving the company entirely to start Discovery Loop, a venture focused on automating machine learning, science, and engineering to accelerate discoveries.

Taking over many of Hassabis's operational duties is Koray Kavukcuoglu, currently CTO of Google DeepMind, who will serve as senior VP of the unit and report directly to Pichai. Departing alongside Dean are Google senior fellow Sanjay Ghemawat, DeepMind VP Oriol Vinyals, and Google Brain co-founder Quoc Le. These exits represent a significant brain drain from Google's AI research ranks. The market reaction was immediate: Google's stock dropped roughly 4% on the news, despite Pichai's careful framing. Dean, reflecting on his tenure, noted Google grew from 25 to 190,000+ people during his time. Discovery Loop's immediate priorities are hiring a founding team and finding office space, but Dean emphasized the long-term ambition: applying automated experimental loops across many fields of science and engineering.