Global Tech Stocks Plunge Most Since March in Test of AI-Driven Rally

What happened

Asian tech tumbled 6% on June 23 — the biggest drop since March 9. South Korea's Kospi plunged 10% (triggering circuit breakers twice), Samsung and SK Hynix fell >12%, Nikkei -3%. Nasdaq futures -2.69%, S&P futures -1.45%.

Context and impact

First major test of 2026's AI-driven rally. Multiple triggers: rate-hike fears, SpaceX share weakness, and crucially reports that SK Hynix is scaling back HBM4 expansion — read as cooling AI chip demand. The market is now stress-testing whether AI-infrastructure-led growth is sustainable or overshoot.

Details

• Kospi -10% (2x circuit breaker)
• Samsung / SK Hynix -12%+
• SK Hynix scales back HBM4
• Nikkei -3%, Nasdaq futures -2.69%
• Largest move since March 9, 2026