S&P 500 momentum rallies near highs may signal weaker returns ahead: Goldman

Goldman Sachs warned that the AI-driven momentum trade may be near an inflection point, citing 14 S&P 500 record highs in the past month and a 25% rise in its Momentum factor over three months. The bank said historically similar episodes near all-time highs often preceded softer equity returns over the following months, though current gains are supported by rising earnings estimates. S&P 500 EPS forecasts for 2026 and 2027 were both revised up 8% year-to-date, with Consumer Staples highlighted as a lower-exposure alternative to AI and macro growth risk.

Analysis

This is less a simple “AI bubble” call than a regime-risk warning: when breadth is this narrow, marginal buyers become momentum-chasers rather than fundamental allocators, which makes the tape fragile to any earnings or capex disappointment. The second-order effect is that the market’s leadership group is now self-referential — AI capex expectations are supporting earnings estimates, which in turn justify higher multiples, but that loop can break quickly if hyperscaler spending normalizes or if financing costs climb.

The biggest near-term hazard is not an immediate crash but a rotation failure. If mega-cap tech stalls, crowded long-only and hedge fund positioning can force de-grossing into the highest-beta parts of the market first, while the “cheap” laggards may not rally enough to save the index because they lack the earnings catalyst needed to attract institutional sponsorship. That makes the next 1-2 months more vulnerable than the next 12 months: momentum typically persists briefly before mean-reverting, but the reversal is usually disorderly once breadth stops improving.

The contrarian nuance is that the setup is not purely speculative because estimate revisions are still positive; that reduces the odds of a classic 2000-style unwind. However, the market may be underpricing the symmetry of outcomes: if AI spend merely meets, rather than beats, current expectations, the valuation multiple compression on the winners can outpace any benefit to the laggards. The best defense is to own earnings revision winners with low AI and macro beta, not simply “cheap” stocks.

On the macro side, a geopolitical escalation would matter less through direct defense exposure and more through rates, energy, and risk-premium channels. Higher oil would reinforce inflation stickiness, which is especially dangerous for duration-sensitive growth leaders already trading as bond proxies; that raises the probability that a tech drawdown becomes a broader factor unwind rather than a sector rotation.

Key Decisions for Investors

• Reduce gross exposure to crowded momentum longs over the next 2-4 weeks; especially trim mega-cap AI beneficiaries with stretched positioning. Use any additional index strength to cut, not add, unless breadth materially improves.
• Initiate a pair trade: long XLP or other low-beta consumer staples basket vs short equal-dollar basket of mega-cap AI leaders for 1-3 months. Thesis: staples have lower estimate risk and less sensitivity to AI capex disappointment; target 5-8% relative outperformance with tight stop if breadth expands.
• Buy downside protection on QQQ or SMH via 1-3 month put spreads, funded by selling out-of-the-money calls. Risk/reward favors hedging a crowded factor reversal rather than outright shorting the index.
• Add names with positive earnings revisions but low AI and macro sensitivity on pullbacks; favor defensives and idiosyncratic growers over index-weighted winners. This is a quality-without-duration trade, not a momentum chase.
• If geopolitical risk escalates and crude rips, rotate part of growth exposure into energy and inflation beneficiaries; avoid adding to long-duration tech into a higher-oil/higher-rate impulse.