Alphabet shares fell approximately 4% after Demis Hassabis stepped back from running day-to-day operations at Google DeepMind to focus on broader strategy. DeepMind CTO and chief AI architect Koray Kavukcuoglu takes the helm as senior vice president, reporting directly to Sundar Pichai. Hassabis moves to chair of Google DeepMind and chief scientist of Alphabet, while continuing to lead Isomorphic Labs. Pichai stated the restructure allows Hassabis to focus on AGI, scientific strategy and future vision, while Kavukcuoglu takes charge of Gemini, frontier research and developer teams. Additionally, 27-year Google veteran Jeff Dean is joining senior fellow Sanjay Ghemawat to launch an independent AI, science and engineering public-benefit corporation, with Google remaining a founding investor and key research partner. The share decline reflects the rest of the announcement, including Dean’s departure and reports that several senior Gemini leaders are also leaving. Gemini currently reaches over 950 million monthly users, and new releases including Gemini 4 are in the pipeline. The market reaction highlights three concerns: execution risk for Kavukcuoglu, talent retention amid senior researcher departures, and strategic coherence.