South Korea's KOSPI triggered a circuit breaker during a broad Asian equity selloff driven by a sharp rotation out of AI-related names. The move echoes the pattern seen after previous AI-hype corrections — crowded positions in semiconductor and memory names (Samsung, SK Hynix) unwinding quickly once sentiment turns, amplified by index-level forced selling. Circuit breaker triggers on the KOSPI are rare and signal unusually concentrated, fast-moving selling pressure.

The key question now is whether contagion spreads to U.S. AI proxies — Nvidia, Broadcom, TSMC ADR, and the broader SMH ETF — when U.S. markets open. Historically, KOSPI AI-led drops have preceded short-term weakness in U.S. semis but also created mean-reversion setups within 5–10 sessions if the fundamental thesis (data center capex, sovereign AI spending) remains intact. Watch NVDA pre-market, SMH open, and any follow-through commentary from U.S. mega-cap tech.