Google's AI leadership split at the top and Jeff Dean left after 27 years.

Alphabet reorganized August 5: Demis Hassabis stepped down as Google DeepMind CEO to become chairman and Alphabet's first chief scientist, with CTO Koray Kavukcuoglu taking day-to-day control as an SVP reporting to Sundar Pichai. Jeff Dean is leaving to cofound Discovery Loop, a public benefit corporation automating ML, science and engineering research, with Google as an early investor. Sanjay Ghemawat, Oriol Vinyals and Quoc Le are also out. Shares fell roughly 4%, and reporting ties it to model delays and a pivot toward agentic systems over specialized tools. Pair with SemiAnalysis on Gemini's token-growth deceleration and the picture is consistent.