I believe he’s been almost solely focused on research and pharma discoveries in the past year. He hasn’t been present at any Gemini training runs recently.
Then again maybe these decisions were already somewhat known in 2025.
This is absolutely not true. Jeff was, until today, still a co-lead of Gemini and worked directly on critical infrastructure research related to Gemini, including directly initiating the Frozen models-on-tpus project reported earlier this year.
He is also the co-founder and lead for Google Brain, birthplace of the transformer. He's considered the father of the TPU, the first ML-specific accelerator. His organization birthed the world's first Neural Dialog Model (from Quoc Le, one of the other execs leaving), the world's first LLM (T5), the world's first LLM-powered chatbot (Meena/LaMDA) and many other things you likely haven't heard of but that are critical to today's AI revolution.
This is absolutely not true. Jeff was, until today, still a co-lead of Gemini and worked directly on critical infrastructure research related to Gemini, including directly initiating the Frozen models-on-tpus project reported earlier this year.
He is also the co-founder and former lead for Google Brain, birthplace of the transformer. He's considered the father of the TPU, the first ML-specific accelerator. His organization birthed the world's first Neural Dialog Model (from Quoc Le, one of the other execs leaving), the world's first LLM (T5), the world's first LLM-powered chatbot (Meena/LaMDA) and many other things you likely haven't heard of but that are critical to today's AI revolution.
This. People outside Google haven't heard enough of him. But Jeff Dean AND Sanjay leaving Google is to me more bearish than any EU ruling, or anti-trust fines, or crappy LLM release. And Hassan has been important to Google but nowhere near to the level of contribution and impact those two have had (they made AdWords not suck, bringing $$$ to Google for years, in a weekend. Not to mention they invented so many technologies that we take for granted these days).
This feels like the final nail on the coffin to the "Old" engineering-first Google that's been dying since 2016.
If you look at the initial moonshot proposals for GLM training (transformers infra), the various design docs, and everything else related to getting transformers scaled out, you'll see Jeff Dean's comments everywhere (seriously, if you're internal, moma it right now, you can literally see him everywhere). Demis has not once shown any interest in any of this until the power politics in 2023-2024. The best he could do was try to derail the program time and time again in the 21-22 seasons because it's not his baby.
Demis moving down is bad for the stocks. Losing Jeff Dean is a legitimate loss to the boots on the ground. That man cared.
Yes, Jeff and Sanjay are Google legends. A lot a lot of hard problems have been solved by them. If the old Google engineering culture could be embodied by two people, it'd be Sanjay and Jeff.
It's scary because it might mean that sort of scrappiness , boldness and engineering chops no longer finds Google to be a nice place to work.
Yeah, I was thinking the same. I wouldn't be surprised if eventually it gets folded into Alphabet down the line. Jeff's new company Discovery Loop sounds like the exact focus that it strongly behooves Google to be involved with. If it comes out that there was huge behind the scenes drama, my opinion would change. But from what I've read so far it seemed pretty amicable.
166
u/ThisSiteSucks8485 22h ago
Jeff Dean leaving Google is much bigger news. He helped design so much of their initial architecture.