The AI trade just had its worst day in months, and it started 7,000 miles from Wall Street.
On June 23, South Korean chipmakers SK Hynix and Samsung Electronics each plunged more than 12%, dragging the country’s Kospi index down roughly 10% and triggering circuit breakers that halted trading entirely. The carnage spread fast. Nasdaq 100 futures dropped about 2.6% in early US trading, S&P 500 futures fell 1.4%, and the European Stoxx 600 tech index shed 3.1%.
What happened in Asia
The selloff centered on memory chip giants that had been among the biggest beneficiaries of the AI infrastructure buildout. SK Hynix, a dominant supplier of high-bandwidth memory used in AI accelerators, and Samsung Electronics, the world’s largest memory chipmaker, both saw their shares crater by double digits in a single session.
South Korea’s Kospi index, heavily weighted toward semiconductors, fell hard enough to trip automatic circuit breakers. Trading was paused to let participants catch their breath, but when it resumed, sellers were still in control.
