S&P 500 concentration hits historic highs as AI stocks dominate
The U.S. stock market is experiencing historic concentration, with AI-related stocks commanding 49% of the S&P 500 at their peak. Since late February, the index gained 8.03%, while non-AI stocks rose only 1.04%. Year-to-date, the S&P 500 is up 8.35%, the Nasdaq Composite 11.42%, and the Dow Jones 5.83%.
*this image is generated using AI for illustrative purposes only.
The U.S. stock market is displaying a historic level of concentration, with artificial intelligence (AI) stocks driving the S&P 500 to impressive heights while the remainder of the market stalls. According to an analysis by Jim Bianco, president of Bianco Research, the 500 stocks without AI-related companies are up just 1.04% since late February, compared to the broader index's 8.03% gain. This divergence marks the most concentrated the market has been on a single theme since the railroad stocks of the late 19th century.
Market Concentration and AI Dominance
At their peak, AI-related stocks commanded a staggering 49% of the S&P 500. Bianco warned that this market density is poised to climb even higher when companies such as Anthropic, OpenAI, and Space Exploration Technologies Corp. (NASDAQ: SPCX) are listed. The performance gap between AI enablers and ordinary corporations has widened significantly, creating a market distortion not seen in over a century.
Performance Gap During Volatility
The decoupling became evident during a brief market correction between June 2 and June 10. During this period, the broader S&P 500 corrected by roughly 4.5%. Conversely, the 500 stocks excluding AI actually rose during that exact window, highlighting the divergence in performance.
Year-to-Date Index Performance
The S&P 500 index has advanced 8.35% year-to-date. Other major indices have also posted gains:
| Index | Year-to-Date Gain |
|---|---|
| S&P 500 | 8.35% |
| Nasdaq Composite | 11.42% |
| Dow Jones | 5.83% |
Major ETFs tracking these indices closed higher on Friday. The SPDR S&P 500 ETF Trust (NYSE: SPY) ended up 0.54% at $741.75, while the Invesco QQQ Trust ETF (NASDAQ: QQQ) was higher by 0.59% to $721.34. The State Street SPDR Dow Jones Industrial Average ETF Trust (NYSE: DIA) closed 0.73% higher.
What are the potential risks to market stability if AI stocks experience a sudden correction?
How might the upcoming IPOs of Anthropic, OpenAI, and SpaceX further impact market concentration?
Could the performance gap between AI and non-AI stocks trigger a shift in investor sentiment toward broader diversification?
19
Access Market Heat-map & Insights 
Create, Save & Share your Screener 
Use 200+ Screening Filters 
