The broad S&P 500 index fell 0.4 percent, while the Dow Jones industrial average and the tech-heavy Nasdaq composite index lost 0.5 percent.
After last week's clear stock market rally, several technology companies strongly linked to AI lost value.
Semiconductor company Nvidia, the world's most valuable listed company, fell 1.2 percent, software company Palantir fell 2.4 percent and cloud services company Oracle fell 1.3 percent.
Facebook owner Meta, down 0.7 percent, and electric car manufacturer Tesla, down 3.3 percent, were also among the bigger losers.
Chris Larkin, chief investment officer at online stockbroker Etrade, points to the strong gains earlier this year, but also to the great importance of the technology sector.
If stocks are to finish another year of double-digit gains with a high tail move, they will likely need the technology sector to do much of the heavy lifting, he says.
