Google parent Alphabet plunged as much as 7% on Monday after the departure of two of its most prominent AI researchers raised Wall Street’s fears that it’s falling behind key rivals.

Google lost senior research scientist and Nobel Prize winner John Jumper, who announced late Friday he was exiting DeepMind AI lab for a role at Anthropic. That news came just days after another key executive Noam Shazeer, who served as co-lead of Google’s flagship Gemini AI models, ditched the company for a role at OpenAI.

The high-profile exits “are raising the concern that Google is losing the war for talent at the frontier of AI,” Gil Lauria, the head of tech research at DA Davidson, told The Post.

“Google had the state-of-the-art model for a few weeks last year which helped it get credit as an AI winner but has fallen off since, and these departures may mean it is falling behind,” Lauria added.

The stock plunge threatened to erase some $270 billion in value in a single day for Google, which was on pace for its worst finish in a year as of midday trading. Google’s decline outpaced the tech-heavy Nasdaq index as well as losses at rivals like Meta, which sank 2%, and Amazon which fell about 4%.

Investors also remain concerned about the pace of AI-related spending at tech giants. Google alone has signaled plans to spend $180 billion to $190 billion in fiscal 2026, with much of that money earmarked for AI compute and data centers.

“Simply said, the market is drawing a sharp line between AI spenders and AI earners,” said Dave Wagner of Aptus Capital Advisors. “The big spending hurts the hyperscalers’ margins, while those massive hardware orders directly benefit memory manufacturers.”

The loss of “key AI research to a close competitor” didn’t help, according to Wagner.

The tech sector’s down day also followed the publication of a Wall Street Journal interview with Microsoft CEO Satya Nadella, who aimed harsh words at major companies while suggesting the US economy should avoid becoming dependent on just a few AI models.

Nadella outlined a vision to make more low-cost AI models available to customers via Microsoft’s new “Copilot Cowork” tool.

Google and other leading US AI firms may also be facing pressure from open-source Chinese models, such as those made by DeepSeek and z.AI, which are competing neck-and-neck in terms of capabilities while in many cases being  far less expensive than leading subscription-based American models.