Index slides to intraday low of 8,126 before paring losses; profit-taking in Samsung Electronics, SK hynix hammers semiconductor heavyweights; retail net purchases of 8.17 trillion won fail to stem decline

A display board at Hana Bank's dealing room in Jung-gu, Seoul, shows Kospi and other market data on Friday. [Yonhap]
A display board at Hana Bank's dealing room in Jung-gu, Seoul, shows Kospi and other market data on Friday. [Yonhap]

The Kospi tumbled more than 5 percent on Friday, dragged down by profit-taking in semiconductor heavyweights and simultaneous selling by foreign and institutional investors, closing at the 8,411 level. The index fell as much as 9 percent intraday — triggering both a sell-side sidecar and a circuit breaker in quick succession — before recovering some of its losses in the afternoon.

According to Korea Exchange, the Kospi closed down 519.09 points, or 5.81 percent, at 8,411.21. The index opened 117.12 points, or 1.31 percent, lower at 8,813.18 and briefly trimmed losses to 8,861.70 in early trade, but intensifying selling pressure pushed it to an intraday low of 8,126.84.

At its intraday low, the Kospi had fallen 9.00 percent. Volatility-control mechanisms were triggered in rapid succession: a sell-side sidecar was activated at around 11:12 a.m., followed by a Level 1 circuit breaker at around 12:10 p.m.

Friday marked the fifth time this year that a circuit breaker has been triggered on the Kospi. The mechanism halts trading on the main bourse for 20 minutes when the index falls more than 8 percent below the previous session's closing price for at least one minute. Earlier triggers this year came amid the US-Iran crisis on March 4, a surge in oil prices driven by Middle East tensions on March 9, a sharp drop in semiconductor stocks on concerns over US interest rate hikes on June 8, a sell-off in US technology stocks on June 23, and a sell-off in US big-tech stocks on June 26.

Foreign and institutional investors led the decline. On the main bourse, foreign investors recorded net selling of 4.65 trillion won ($3.01 billion), while institutions net sold 3.77 trillion won. Retail investors absorbed the selling with net purchases of 8.17 trillion won, but it was not enough to halt the index's fall.

The day's plunge was driven largely by Samsung Electronics and SK hynix, which each fell around 10 percent intraday. Analysts attributed the sharp moves to a concentration of short-term profit-taking after semiconductor stocks had surged on the back of Micron's strong earnings and optimism over AI memory chip demand.

Samsung Electronics closed down 5.30 percent at 339,500 won, while SK hynix tumbled 8.36 percent to 2.67 million won. SK Square, whose value is closely tied to SK hynix's share price, fell 9.43 percent — the steepest drop among the top 10 stocks by market cap. Samsung Electronics preferred shares (-6.17 percent), LG Energy Solution (-5.82 percent), Samsung C&T (-4.72 percent) and Hyundai Motor (-4.47 percent) also posted broad losses. Samsung Life (-3.24 percent) and Samsung Biologics (-3.10 percent) each fell more than 3 percent, while Samsung Electro-Mechanics edged down just 0.20 percent, limiting its losses relative to peers.

With the two semiconductor giants accounting for a large share of the Kospi's total market cap, their volatility translated directly into index-level swings. The index's decline, contained to around 1 percent in early trade, widened to 9 percent intraday as selling pressure on the large-cap semiconductor names intensified.

Concerns about a potential slowdown in memory chip demand also weighed on investor sentiment. Han Ji-young, a researcher at Kiwoom Securities, said noise had emerged suggesting that worries over declining memory demand could dampen hyperscaler companies' willingness to invest, adding that short-term profit-taking following a sharp two-session rebound also amplified selling pressure.

The Kosdaq also closed lower, falling 36.44 points, or 4.10 percent, to 851.37. It opened down 3.38 points, or 0.38 percent, at 884.43, slid to an intraday low of 838.53, then pared some of its losses.

On the Kosdaq, foreign and institutional investors recorded net purchases of 341.9 billion won and 307.4 billion won, respectively, while retail investors net sold 664 billion won. Total trading value on the Kosdaq reached 8.21 trillion won, with volume of 717.29 million shares.


kacew@heraldcorp.com