Samsung Electronics and SK hynix 'Plunge' 7% and 10%... KOSPI Barely Holds 6,000

KOSPI jolts as losses top 6% intraday
Foreign selling triggers a sell-sidecar
In a phase of testing for a short-term bottom

The KOSPI barely held above the 6,000 mark.

Employees work at the dealing room of Hana Bank's headquarters in Jung-gu, Seoul, on the 13th, as the KOSPI continued its decline for a fifth consecutive trading day. The index plunged more than 5% at one point during the session, triggering a sell-sidecar for the first time in 55 days, since August 19. 2026.10.13 Photo by Kim Hyunmin

The KOSPI closed at 6,035.35 on the 13th, down 348.89 points (5.46%) from the previous session. It fell below the 6,000 mark at one point during the session. As the market plunged, a sell-sidecar was triggered at 9:47:58 a.m. It was the first sidecar activation in the KOSPI market since August 20, and the first sell-sidecar activation since August 19.

U.S. stocks ended mixed overnight as international oil prices rose and selling of memory semiconductor shares continued. On October 12 (local time), the Dow Jones Industrial Average rose 195.60 points (0.38%) from the previous session to close at 51,850.55. The S&P 500 fell 4.30 points (0.06%) to 7,807.24, while the Nasdaq Composite dropped 120.27 points (0.44%) to finish at 27,245.90. Memory semiconductor-related shares were particularly weak. News that China's ChangXin Memory Technologies (CXMT) had advanced its DRAM technology and would unveil next-generation server products by the end of the year weighed on the market.

Retail and institutional investors were net buyers of KRW 2.2292 trillion and KRW 1.6889 trillion, respectively. Foreign investors were net sellers of KRW 4.5266 trillion. Foreign investors' selling continued for a sixth consecutive trading day.

By sector, electricity and electronics (-7.61%), manufacturing (-6.28%), financials (-3.66%), machinery and equipment (-3.13%), and insurance (-2.48%) declined.

Among the top companies by market capitalization, Samsung Electronics (-7.39%), SK hynix (-10.09%), Samsung Electronics preferred shares (-6.69%), SK Square (-12.91%), and Samsung Electro-Mechanics (-8.34%) fell.

The KOSDAQ closed at 837.03, down 12.16 points (1.43%) from the previous session. Retail investors were net sellers of KRW 190.8 billion. Foreign and institutional investors were net buyers of KRW 139.8 billion and KRW 42.9 billion, respectively.

By sector, non-metallic minerals (-3.86%), general services (-3.09%), distribution (-2.70%), pharmaceuticals (-2.51%), and electricity and electronics (-2.24%) declined.

Among the KOSDAQ's top companies by market capitalization, Alteogen (-2.03%), EcoPro BM (-2.08%), and Rainbow Robotics (-1.92%) fell, while Jusung Engineering (3.56%) and EcoPro (1.31%) rose.

“The market is plunging amid negative factors that were already known,” said Han Ji-young, a researcher at Kiwoom Securities. “Investor sentiment has weakened and trading has dried up, apparently leaving prices less able to withstand selling pressure.” She added, “It is worth remembering that the market briefly fell below the 200-day moving average during only a few trading sessions in the July crash. We are in a phase of testing for a short-term bottom, and joining the sell-off now that the 6,000 level has been breached could expose investors to greater upside risk.”

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