Global stock markets entered a risk-off phase on Tuesday, with futures tied to the S&P 500 and the Nasdaq 100 under pressure after investors began to pare back crowded positions in companies linked to artificial intelligence.
Across Asia overnight, major benchmarks fell and set a negative tone for European trading. The Nikkei 225 and Hang Seng moved lower, while South Korea's KOSPI at one point recorded a nearly 10% decline as AI-related winners were hit hard. Samsung Electronics and SK Hynix, two large beneficiaries of the AI investment wave, saw steep share-price moves downward.
Market strategists noted the extent of the recent rally and suggested the KOSPI's rebound had reached extreme levels before reversing. Citi strategists led by David Chew highlighted that the KOSPI's readings are now back to extremes after its recent advance.
In Europe, the Euro Stoxx 600 extended losses during the morning session, falling around 1.1%, and U.S. futures subsequently deepened the decline, pointing to a potentially sharp opening for Wall Street.
UBS strategists, led by Gerry Fowler, cautioned investors that growing recognition of crowding risks and what they described as a 'same bus' dynamic has begun to erode tactical conviction. The strategists observed that although the market still broadly believes in the structural AI story, some hedge funds and other investors have started trimming exposure as the margin for additional upside narrows relative to risk.
The 'same bus' description reflects a concentration of institutional capital into a compact group of companies that supply or enable AI: semiconductor designers, hyperscale cloud providers, memory-chip manufacturers, and other infrastructure-focused names. That concentration left the market sensitive to repositioning once profitable longs became concentrated.
Fowler also warned of the potential for capex upgrades to slow as activity reaches a 'speed-limit,' a development that could stall the stream of upward revisions in the supply chain. If capital-expenditure announcements from hyperscalers that had driven analyst estimate upgrades through 2025 begin to plateau, the earnings-revision engine that has supported premium valuations across AI supply-chain stocks could lose momentum. In that scenario, expensive and crowded positions could become vulnerable to underperformance.
Signs of this vulnerability had begun to appear before Tuesday's widespread move. Technology stocks exerted downward pressure on the Nasdaq Composite and the S&P 500 ahead of the global selloff, providing an early indication of rising stress in risk assets.
Citi's Chew noted that bullish positioning on the Nasdaq remained extended in both size and profitability, with many long positions sitting deeply in profit. That concentration of profitable longs leaves the market exposed, increasing downside risk if those positions are reduced.
For market participants, a central question is whether the tactical trimming of crowded positions accelerates into broader, disorderly selling or whether buyers step in to defend the longer-term structural thesis supporting AI-related investments. The trajectory will likely hinge on the emergence of fresh catalysts capable of restarting the upward cycle of estimate revisions.
Two such catalysts highlighted by strategists are further capital-expenditure commitments from hyperscalers or concrete evidence that AI monetization is outpacing infrastructure costs. Absent those signals, the fundamental rationale for consensus-long positions in expensive AI-supply-chain names may weaken materially.
Among individual names, Micron Technology was noted as one of the stronger performers over the prior 12 months and is scheduled to report earnings on Wednesday after the market close. That report is likely to attract attention from investors looking for fresh information about demand, pricing, and the pace of revenue conversion in memory markets.
What to watch next
- Whether hedge funds and other large investors continue tactical trimming, amplifying downward momentum.
- Announcements of new hyperscaler capex commitments that could revive upward estimate revisions.
- Micron's upcoming earnings report for signals on memory demand and margin dynamics.