KOSPI plunges 5.28% to 5,383.80 in November 5 close
Published on 11/05/2026 at 18:38 | Editorial responsibility: Rafael Müller, Editor-in-Chief AD HOC NEWSWhat drove the KOSPI selloff
- The KOSPI closed at 5,383.80 on November 5, down 300.00 points, or 5.28 percent, from the previous session.
- Concerns about tighter US AI data-center regulation after the midterm elections pressured semiconductor and related technology shares.
- Foreign investors sold a net 3.39 trillion won of Korean shares, while a sell-side sidecar temporarily halted program trading.
- Samsung Electronics fell 7.57 percent and SK hynix dropped 9.46 percent as the semiconductor-heavy index breached 5,400.
The KOSPI ended its November 5 session at 5,383.80, down 300.00 points, or 5.28 percent, from the previous trading session. The close below 5,400 followed a sharp intraday reversal from an opening decline and marked a broad selloff in South Korean technology shares.
Yonhap News Agency reported that the index opened 1.82 percent lower before extending its losses. A sell-side sidecar was activated at 10:16 a.m. Seoul time, temporarily suspending program trading in KOSPI-listed shares for five minutes. Foreign investors sold a net 3.39 trillion won, while institutions and individuals were net buyers.
AI regulation concerns hit chip stocks
The session's main pressure point was the prospect of tighter regulation of artificial-intelligence data centers in the United States. The Democratic Party's strong showing in the US midterm elections raised concerns that the new Congress could slow data-center construction and, in turn, weaken expectations for AI-related investment and semiconductor demand.
Reuters said data-center companies and equipment suppliers across Asia came under pressure on expectations of tougher regulation. It also reported that the KOSPI was down about 4 percent in morning trading as chip stocks weakened.
The technology concentration of the Korean benchmark amplified the move. Samsung Electronics fell 7.57 percent to 201,500 won, while SK hynix dropped 9.46 percent to 1,264,000 won, according to Yonhap. Other semiconductor and equipment shares also declined, while some non-technology stocks provided limited offsets. Hyundai Motor rose 3.53 percent and Kia gained 5.22 percent, but those advances were insufficient to stabilize the index.
Sharp fall after volatile session
The KOSPI opened at 5,580.09, down 103.71 points from the previous session's 5,683.80 close. It later reached an intraday low of 5,336.88, or 6.10 percent below that comparison level, before recovering part of the loss by the close. The scale of the decline reflected a rapid repricing of semiconductor and AI infrastructure expectations rather than a change in the index's composition.
The November 5 close gives investors a clearer reference point than the earlier intraday readings. The immediate market focus is likely to remain on US policy signals, AI infrastructure spending expectations and foreign positioning in Korean technology stocks. For further KOSPI coverage, see the KOSPI topic page.
