KOSPI closes 3.48% lower at 5,730.74 as AI concerns hit Seoul stocks
Published on 10/30/2026 at 19:00 | Editorial responsibility: Rafael Müller, Editor-in-Chief AD HOC NEWSKOSPI ends sharply lower
- The KOSPI closed at 5,730.74 on October 30, down 206.92 points or 3.48 percent.
- Concerns about the returns on heavy artificial-intelligence investment pressured semiconductor shares after losses on Wall Street.
- A sell-side sidecar was activated after KOSPI 200 futures fell sharply, while foreign investors sold Korean equities.
- Kia and Hanwha Aerospace added to the afternoon pressure after company-specific earnings and outlook concerns.
The KOSPI ended the October 30 session sharply lower as a global technology sell-off renewed concerns about the profitability of artificial-intelligence investment. The benchmark Korea Composite Stock Price Index closed at 5,730.74, down 206.92 points, or 3.48 percent, from the previous session. It opened at 5,760.35, a decline of 2.99 percent, and fell as low as 5,599.42 during the session.
Yonhap News Agency reported that the Korea Exchange activated a sell-side sidecar shortly after 10 a.m. Seoul time. The measure followed a fall of at least 5 percent in the KOSPI 200 Futures Index for at least one minute and temporarily suspended the effectiveness of program sell orders.
AI concerns hit chip shares
The pressure began with losses in U.S. technology stocks. The Korea Times said weaker-than-expected results and guidance from major U.S. technology companies raised fresh questions about the returns on large AI infrastructure budgets. The Nasdaq Composite had fallen 1.38 percent in the preceding U.S. session, while Alphabet declined 12.64 percent.
That backdrop weighed particularly heavily on Korean chipmakers. Samsung Electronics fell 3.02 percent to 225,000 Korean won, while SK hynix lost 7.08 percent to 1.42 million Korean won, according to Yonhap. The decline was broad: Yonhap reported 655 decliners against 232 advancers, with trading volume of 212.76 million shares and value of 19.27 trillion Korean won. Foreign investors sold a net 1.62 trillion Korean won, while institutions and individuals were net buyers.
Company-specific selling broadened
Automakers and defense stocks added to the market's weakness later in the session. Hyundai Motor fell 3.59 percent after lowering its annual sales target and investment plans. Kia dropped 11.73 percent to 95,600 Korean won after reporting weaker-than-expected third-quarter operating profit. Hanwha Aerospace declined 8.42 percent to 696,000 Korean won after earnings were affected by delays in deliveries of K9 self-propelled howitzers to Poland.
The Korean won strengthened against the U.S. dollar, trading at 1,334.3 won per dollar at 3:30 p.m. Seoul time, according to Yonhap. The session's combination of global AI-spending concerns, heavy foreign selling and company-specific earnings disappointments leaves the KOSPI sensitive to further changes in technology valuations and corporate guidance. Further KOSPI coverage is available on the KOSPI topic page.
