Analysis-US tech stock tumble highlights risk of market reliance on megacaps
Turbulence in some of the biggest tech names is reminding investors of one of the major risks to the U.S. stock market's record-setting rally: Reliance on a handful of mammoth companies to power those gains. Investors are scrambling to understand the fallout for the artificial intelligence (AI) investment theme that has been a critical driver for stocks over the past two years after the emergence of a low-cost Chinese AI model rattled markets. Optimism over AI has helped propel shares of chipmaker Nvidia and others of the "Magnificent Seven" megacaps, which combined contributed more than half of the S&P 500's 25% total return in 2024.