Nvidia's Market Dominance Outweighs Half of S&P 500

Nvidia Corp. (NASDAQ:NVDA) has reached a point of dominance in the U.S. stock market where its market capitalization now exceeds the combined value of the smallest 256 companies in the S&P 500. Lance Roberts of Real Investment Advice highlighted this trend, noting that Nvidia alone carries more index weight than these 256 companies together. This concentration underscores how a single stock can outweigh more than half of the benchmark's members.

The current market rally is increasingly narrow, with only 25% of S&P 500 stocks trading above their 50-day moving average. While the S&P 500 gained 2.1% in the third quarter, the equal-weight version of the index fell 2.2%, indicating that the typical stock lost money while the headline index rose. This pattern continued last week, with the S&P 500 slipping 0.3% and the equal-weight index falling 0.7%.

Large asset managers have been warning about this concentration for weeks. Capital Group noted that the 10 largest S&P 500 companies now make up more than 39% of the index, surpassing the dot-com peak of March 2000. CIBC Private Wealth described this level as unprecedented, while J.P. Morgan Asset Management observed that technology and communication services now account for 47% of the index, up from 22% in 2014. Some major global pension funds are already reducing their exposure to U.S. equities due to high valuations and rising AI-driven concentration risk.

Despite its market dominance, Nvidia earned $197.6 billion in operating income over the past 12 months, less than half of the $487.3 billion generated by the 256 smallest S&P 500 companies combined. Nvidia's operating profits match those of the smallest 137 companies in the index, but investors are paying a premium for its growth and higher margins. Nvidia retains about 65 cents of operating profit from every dollar of sales, compared to about 13 cents for the 256 smallest companies, with revenue growing 83% year over year.