The S&P 500 climbed above 6,900 for the first time on October 28, 2025, but nearly 80% of its stocks fell that day. This made it the weakest market breadth ever recorded for a positive session.
This anomaly illustrates the rally’s extreme concentration and raises concerns about market fragility, even as prediction markets show optimism for further gains.
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A Rally Driven by a Few Stocks
As of this writing, the S&P 500 (SPX) traded at 6,890, a modest correction after topping out at 6,911 on Tuesday.
S&P 500 (SPX) Price Performance. Source: TradingViewMarket analysts are calling it one of the strangest rallies in modern history. According to Barchart, almost 80% of S&P 500 stocks declined, marking the worst day of market breadth ever recorded. Meanwhile, the SPX was making new all-time highs.
Bespoke Investment Group confirmed the numbers, calling it the S&P’s worst breadth day ever for an up day. ZeroHedge added that this anomaly will make the history books, as it reflects the most negative market breadth at an all-time high on record.
The rally is being carried almost entirely by AI-driven megacaps. According to the Kobeissi Letter, markets are witnessing a once-in-a-lifetime run. It cited the intersection of one of the biggest technological revolutions in history, deregulation, and trillions of dollars of investment.
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Yet, Kobeissi also cautioned that volatility remains a defining feature of this era.
The rally’s narrowness reflects how concentrated US equity leadership has become, with big tech proving dominant. The gains of a few AI heavyweights are masking widespread weakness, a dynamic that often signals exhaustion in late-stage bull markets.
Still, traders aren’t backing off. Prediction platform Kalshi estimates an 81% probability that the S&P 500 reaches 7,000 by year-end, suggesting investor belief in the power of liquidity and policy optimism to sustain the run.
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Crypto’s Quiet Counterpoint
While Wall Street floats on megacap momentum, crypto watchers are drawing comparisons and distinctions, with analyst Diana Sanchez highlighting the scale gap.
Jamie Coutts, an analyst at RealVision and former Bloomberg Intelligence strategist, believes crypto markets are growing beyond these liquidity-driven cycles.
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In contrast, Mark Cullen of AlphaBTC observed that crypto prices remain buoyed by macro optimism.
If the S&P’s historic surge reflects liquidity excess and AI euphoria, crypto may be quietly positioning itself for a different kind of growth, one rooted in infrastructure, independence, and real utility.
While Wall Street’s rally narrows, blockchain’s breadth may be widening quietly.
Source: https://beincrypto.com/sp500-weak-breadth-crypto-shift/

