Goldman Sachs has warned that a slowdown in artificial intelligence investment could wipe as much as 20% off U.S. stock market valuations. Analyst Ryan Hammond wrote that if long-term growth expectations revert to early 2023 levels, the S&P 500’s multiple would face 15–20% downside.

AI spending is currently strong, but Hammond noted some analysts expect growth to decelerate sharply in late 2025 and into 2026.

The concern stems from the outsized role of AI-linked firms in the market:

Nvidia alone represents 7% of the S&P 500, while the top eight AI-heavyweights make up more than 36%. Even outside the top 10, firms like Oracle, Palantir, and Cisco add to the sector’s weight.

Goldman warns that if the AI trade fades, the S&P 500 could suffer a broad drag.

Goldman isn’t calling an imminent crash, but warns that a future AI spending slowdown could pose a 15–20% risk to S&P 500 valuations, leaving tech-heavy benchmarks vulnerable.