KOSPI, KOSDAQ Trigger Circuit Breakers in Tandem; Losses Narrow Slightly

Circuit Breakers Triggered After 8% Plunge Despite Sidecars

Both the KOSPI and KOSDAQ continued to fall even after sell-sidecars were triggered, prompting circuit breakers to be activated. The declines subsequently narrowed somewhat.

As of 1:45 p.m. on Oct. 15, the KOSPI was trading at 5,591.89, down 416.92 points (6.94%) from the previous trading day. The index opened at 5,673.01, down 335.8 points (5.59%) from the previous session, and a sell-sidecar was triggered seven minutes later. The decline continued, however, and a circuit breaker was triggered at around 12:38 p.m. It was the first such activation in two and a half months, since July 29.

A Level 1 circuit breaker is triggered when the index remains more than 8% below the previous day's level for one minute. Once activated, trading is halted for 20 minutes. Order entry is also suspended, except for cancellation orders. After trading resumes, transactions are conducted through a call auction for 10 minutes.

Foreign investors' selling is driving the decline. They recorded net sales of KRW 3.3781 trillion. By contrast, individual investors and institutions recorded net purchases of KRW 1.2814 trillion and KRW 1.5939 trillion, respectively.

With the KOSPI's 5,500 level also in jeopardy during intraday trading, a display board in the dealing room at Hana Bank's headquarters in Jung-gu, Seoul, shows the KOSPI, KOSDAQ and won-dollar exchange rate on Oct. 15. The KOSPI opened at 5,673.01, down 335.8 points (5.59%) from the previous day's close of 6,008.81, and extended its losses. 2026.10.15 Photo by Jo Yongjun

Among the KOSPI's largest companies by market capitalization, shares were lower except for Samsung Biologics (5.2%), KT&G (4.3%), Celltrion (1.6%), Industrial Bank of Korea (0.9%), Woori Financial Group (0.8%), HMM (0.4%), and Hana Financial Group (0.1%). Samsung Electro-Mechanics fell 15%, while Hyosung Heavy Industries (-14.4%), Doosan (-13.2%), LS ELECTRIC (-12.3%), SK hynix (-10.5%), and HD Hyundai Electric (-10.5%) also declined.

At the same time, the KOSDAQ was trading at 763.15, down 60.73 points (7.37%) from the previous trading day. The index opened at 784.45, down 39.43 points from the previous session. A sell-sidecar was triggered 12 minutes later. As the decline continued, a circuit breaker was activated at around 12:23 p.m., earlier than on the KOSPI, halting trading for 20 minutes.

Individual investors and institutions recorded net sales of KRW 12.8 billion and KRW 29.1 billion, respectively. Foreign investors, by contrast, recorded net purchases of KRW 35.9 billion.

Among the KOSDAQ's largest companies by market capitalization, shares were also weaker except for Silicon2 (0.4%). TES fell 16.2%, while Eugene Technology (-15.4%), ISC (-14.3%), PSK (-14.1%), and Wonik IPS (-13.9%) also declined.

This content was produced with the assistance of AI translation services.