KOSPI falls 3.7% to under 6,400

By Joseph Kwak Posted : October 12, 2026, 17:31 Updated : October 12, 2026, 17:31
Graphics by AJP Song Ji-yoon

SEOUL, October 12 (AJP) - Foreign investors sold South Korean stocks for a 10th straight session on Monday, pushing the benchmark Korea Composite Stock Price Index (KOSPI) below 6,400.

The selling continued two trading days after Samsung Electronics posted the largest quarterly operating profit ever reported by a Korean company.

The KOSPI shed 241.7 points, or 3.6 percent, to 6,384.2.

Foreigners net sold 2.02 trillion won ($1.51 billion) of shares on the main board, bringing their October total to nearly 10 trillion won. Samsung Electronics and SK hynix each fell more than 4 percent, and the tech-heavy secondary KOSDAQ lost 4.8 percent.

Samsung Electronics dropped 4.4 percent to 250,500 won ($187.8).

SK hynix fell slightly harder with a 4.5 percent drop to 1,605,000 won ($1,203.1).

Holding company SK square, the largest shareholder in SK hynix, lost 6.3 percent to 984,000 won ($737.6). That was the steepest drop among the 10 largest stocks on the main board by market value.

Samsung reported on Thursday a preliminary third-quarter operating profit of 107.4 trillion won ($80.5 billion), the first time a Korean company has topped 100 trillion won in a single quarter. Foreigners still sold 2.43 trillion won of Korean shares that day.

Local brokerages have tied the run of foreign selling to rising U.S. borrowing costs. The U.S. 10-year Treasury yield stood above 5.2 percent on Monday.

Retail investors took the other side, buying a net 1.47 trillion won ($1.10 billion). Institutions sold 110.7 billion won ($83.0 million).

Decliners beat gainers 720 to 166, and the main index in Seoul traded below Thursday’s close all session. Korean markets were shut Friday for Hangeul Day.

The KOSDAQ fell more steeply than the main board, shedding 43.1 points to 849.2.

Tokyo markets were closed for Sports Day, a national holiday. The Nikkei 225 last finished Friday at 69,030.9, little changed.

The won strengthened 9.9 won to 1,334.1 per dollar.

Samsung’s earnings have not slowed the foreign exit. Until U.S. yields ease, Korean retail buyers are left absorbing what foreign funds sell, and they have not yet put a floor under the market.

AJP Takeaways

  • Foreign investors net sold 2.02 trillion won ($1.51 billion) of South Korean shares on Monday, pushing the KOSPI below 6,400.
  • The selling hit the two chip leaders. Samsung Electronics fell 4.4 percent and SK hynix 4.5 percent, two trading days after Samsung reported a 107.4 trillion won ($80.5 billion) quarterly operating profit.
  • Retail investors bought a net 1.47 trillion won ($1.10 billion), but the KOSPI still lost 3.6 percent to 6,384.2.

Tags: Samsung Electronics; SK hynix; SK square; Korea Composite Stock Price Index (KOSPI); KOSDAQ; Nikkei 225; U.S. Treasury yield; won-dollar exchange rate; foreign investors; Hangeul Day

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