KOSPI Closes Down 6%... Intraday Sell Sidecar Triggered

KOSDAQ Also Continues Downtrend
Foreign and Institutional Investors Turn Net Sellers

The KOSPI index plunged by over 6%. While the KOSDAQ showed some signs of recovery after opening lower, it ultimately also closed down.

On August 19, at the Korea Exchange, the KOSPI closed at 6,471.17, down 5.8% from the previous session. The index opened at 6,528.77, a decrease of 4.96%. At 9:06 a.m., a sell sidecar—temporarily halting program sell orders for five minutes—was triggered in the stock market. The KOSPI hovered around the 6,500 level before falling into the 6,400s.

Foreign investors and institutional investors recorded net sales of 3.4883 trillion won and 1.3244 trillion won, respectively. In contrast, individual investors were net buyers, purchasing a net 4.6368 trillion won.

By sector, with the exception of construction (up 1.84%) and pharmaceuticals (up 0.01%), all sectors declined. Utilities and electronics dropped 7.68%, followed by manufacturing (down 6.36%), insurance (down 5.89%), finance (down 4.81%), securities (down 4.6%), and distribution (down 4.45%).

Among major market capitalization stocks, most closed lower except for Hanwha Aerospace (up 2.7%), LG Energy Solution (up 1.8%), Samsung Biologics (up 0.8%), and LIG Defense & Aerospace (up 0.1%). SK Square plunged 11.5%, alongside declines in Samsung Life Insurance (down 11.1%), SK hynix (down 9.7%), Samsung Electronics (down 7.8%), SK Inc. (down 6.6%), and Korea Zinc (down 6%).

On August 19, 2026, in the dealing room at the headquarters of Hana Bank in Jung-gu, Seoul, the KOSPI, KOSDAQ, and won/dollar exchange rate are displayed as the KOSPI saw an early session plunge of over 6%, triggering a temporary suspension of program sell orders (sidecar). Photo by Jo Yongjun

The KOSDAQ opened at 810.08, down 2.89% from the previous session. It rebounded to 840.5 as of 10:10 a.m. before fluctuating and ultimately closed at 824.46, down 1.17% from the previous session.

Foreign investors and institutional investors recorded net purchases of 14.8 billion won and 49.9 billion won, respectively, while individual investors sold a net 71.6 billion won.

Among major market cap stocks, results were mixed. Hanamicron fell 6.6%, with further declines by Padu (down 6.4%), SPG (down 6%), and TSE (down 4.8%). However, HPSP gained 7.1%, while ISC rose 6.1%, Peptron 3.2%, and Seojin System 3.2%.

Kyungmin Lee, a researcher at Daishin Securities, stated, "There was a correction centered on the semiconductor sector, which had previously led the sharp rebound, and the stock market continued to show a weak trend. External factors such as U.S. Treasury yields and uncertainties in the Middle East also exerted downward pressure."

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