KOSPI plunges 5.28% to 5,383.80 amid US AI regulation fears
Published on 11/05/2026 at 13:06 | Editorial responsibility: Rafael Müller, Editor-in-Chief AD HOC NEWSKOSPI ends amid AI policy fears
- The KOSPI closed at 5,383.80 on November 5, 2026, down 5.28 percent from the previous session.
- Concerns about tighter US rules for artificial intelligence data centers pressured semiconductor shares and triggered a sell-side sidecar in Seoul.
- Foreign investors were net sellers of 3.39 trillion Korean won, while Hyundai Motor and Naver advanced against the broader decline.
The KOSPI closed sharply lower on Thursday, November 5, 2026, as concerns about tighter US regulation of artificial intelligence infrastructure triggered heavy selling in South Korean technology shares. The benchmark index ended at 5,383.80, down 300.00 points, or 5.28 percent, from the 5,683.80 close recorded on November 4. The closing figures were reported by Yonhap News Agency.
US election reshapes technology outlook
The index opened 1.82 percent lower and extended its losses during the morning. Yonhap reported that the Korea Exchange activated a sell-side sidecar at 10:16 a.m. to suspend program trading in KOSPI-listed shares for five minutes. The move followed a landslide Democratic victory in the US midterm elections, which raised expectations that the new Congress could tighten rules affecting artificial intelligence data centers and potentially slow related investment.
The concern was concentrated in the semiconductor value chain. Samsung Electronics fell 7.57 percent to 201,500 Korean won, while SK hynix dropped 9.46 percent to 1.26 million Korean won. Hanmi Semiconductor declined 9.13 percent and Samsung Electro-Mechanics lost 15.34 percent, according to Yonhap. The pattern indicates that investors were reassessing the demand outlook for chipmakers and equipment suppliers rather than simply responding to the previous session's volatility.
Foreign selling deepens market pressure
Foreign investors were net sellers of 3.39 trillion Korean won, while institutions and individual investors recorded net purchases of 841.8 billion won and 2.28 trillion won, respectively. Declining shares outnumbered advancing shares by 534 to 344, and trading value reached 22.6 trillion Korean won. These figures point to broad participation in the sell-off, with domestic buying only partly offsetting overseas selling.
Several stocks moved against the index. Hyundai Motor gained 3.53 percent to 293,500 Korean won and Kia rose 5.22 percent to 100,800 Korean won. Naver advanced 8.26 percent to 184,900 Korean won, while SK Telecom edged up 0.13 percent. By contrast, refinery and defense shares also weakened as hopes for diplomatic progress in the Middle East and Eastern Europe reduced support for those groups, Yonhap reported.
Volatility remains the central market risk
The session shows how quickly policy expectations can alter the relative performance of Korean sectors. Semiconductor companies remain particularly sensitive to changes in assumptions about data-center investment, while lower oil prices and potential tariff relief may support selected transport and consumer-linked areas. The market's next direction will depend in part on whether foreign selling eases and whether investors distinguish between regulation risk and longer-term demand for artificial intelligence infrastructure.
Further KOSPI coverage is available on the KOSPI topic page.
