Two more senior Gemini researchers, Jonas Adler and Alexander Pritzel, are planning to leave Google for Anthropic, Bloomberg reported Wednesday, citing people familiar with the matter. That makes four prominent AI staffers gone in six days, and the pattern is no longer plausibly random.

Adler worked on Google’s AI coding effort; Pritzel was involved in training AI systems. Both previously collaborated with John Jumper on AlphaFold, the protein-structure system that has predicted more than 200 million structures and that won Jumper the 2024 Nobel Prize in Chemistry. Jumper, a vice president and engineering fellow under DeepMind chief Demis Hassabis, announced his own exit on X on June 19 after nearly nine years; he isn’t expected to start at Anthropic until next year. A day earlier, Noam Shazeer, VP of engineering and co-lead of Gemini, said he was leaving for OpenAI.

The Shazeer departure is the one that stings analytically. Google paid a reported $2.7 billion in September 2024 to license Character.AI’s technology, a deal widely understood as the price of bringing Shazeer back inside. Twenty-one months later, he’s gone again.

Markets noticed. Alphabet shares fell as much as 1.2 percent intraday on June 24, extending what CNBC called the stock’s worst day in more than a year.

A 2025 SignalFire analysis found DeepMind engineers are nearly 11 times more likely to leave for Anthropic than the reverse. That’s not a vibe shift; it’s a structural gradient, and it has been visible in the data for a year. Anthropic declined to comment. Adler, Pritzel, Jumper and Shazeer didn’t respond.

The AlphaFold cohort reassembling inside a competitor is the kind of detail that tends to read, in retrospect, as the moment the org chart stopped holding.

Sources