South Korea's KOSPI plunges 44% from June peak as AI selloff deepens

South Korea's KOSPI has fallen approximately 44% from its June peak, extending a five-month decline as concerns over AI infrastructure spending trigger heavy selling across technology stocks.
The benchmark index dropped 6.02% on Friday, November 6, closing at 5,059.69 after briefly falling as much as 8.8% during the session. The sharp decline triggered a 20-minute trading halt.
The KOSPI lost 11.7% for the week, with semiconductor giants Samsung Electronics and SK Hynix among the hardest-hit stocks. The two companies fell 6.4% and 10.4%, respectively, on Friday.
The selloff followed a steep decline in US technology shares, as investors questioned whether aggressive AI investment plans could face delays, tighter regulation or weaker returns.
Foreign investors sold approximately 2.8 trillion won in South Korean equities during Friday's session, adding to pressure on a market heavily exposed to the global semiconductor industry.
Despite the correction, the KOSPI remains approximately 20% higher year to date, reflecting the scale of its earlier rally.
The reversal highlights how concerns over AI spending are spreading beyond US technology stocks to international markets that supply the hardware behind the industry's expansion.
Source: Reuters, Yonhap News Agency (November 6, 2026)