" Competition for top AI talent has the potential to clobber even the biggest Big Tech stocks, as Alphabet experienced on Monday, the first trading day after John Jumper, a senior research scientist and Nobel Prize winner, said he was leaving Google DeepMind for artificial-intelligence start-up Anthropic.

 
• The Google parent’s stock ended the day down 5%, shaving $225 billion from its market value, the biggest drop for the company ever, according to Dow Jones Market Data. Jumper is leaving after nine years. DeepMind is the backbone of Google’s advanced AI models.

 
• Google praised Jumper’s “significant contributions” to DeepMind’s work and wished him well. Anthropic confirmed to Barron’s that Jumper will be joining it. The AI start-up declined to comment on how it is prioritizing talent acquisition or whether Anthropic plans to make any more high-level hires in the near future.

 
• Jumper helped create AlphaFold, DeepMind’s AI system that predicts protein structures from their amino acid sequences. His departure comes shortly after Noam Shazeer, a vice president of engineering at Google and a key member of the Google Gemini team, said he was leaving for OpenAI.

 
• Big Tech along with AI start-ups Anthropic and OpenAI are currently fighting for the top AI talent in the marketplace as they all vie for superiority. As a result, pay packages have stretched to the hundreds of millions, and big-money acquisitions of smaller rivals have become commonplace.

 
What’s Next: D.A. Davidson analyst Gil Luria said the talent drain from Google raises concerns that it’s losing the war for talent at the frontier of AI. Both Anthropic and OpenAI are planning IPOs, adding to the competition not just for talent but for investor dollars.

 
—Kit Norton