In the regular South Korean market session (09:00–15:30) on September 4, 2026, the KOSPI rose 1.64% to 6,687.21 points, while the KOSDAQ gained 2.95% to 813.50 points. Among tracked stocks, SK Square posted the largest gain at 6.12%, while SK hynix and Samsung Electronics also recorded closing gains that exceeded the indexes’ advances. Hyundai Motor closed unchanged.

Index September 4, 2026 Regular-Session Close Change From Previous Trading Day Data
KOSPI 6,687.21 points +107.73 points(+1.64%) Closing data
KOSDAQ 813.50 points +23.29 points(+2.95%) Closing data

KOSDAQ Outpaces KOSPI in Closing Gain

The KOSPI opened at 6,654.36 points on September 4, 2026, rose as high as 6,746.14 points during the session, and recorded an intraday low of 6,632.77 points. Its regular-session close of 6,687.21 points on September 4, 2026, was above its opening level and up 107.73 points(+1.64%) from the previous trading day. KOSPI closing data for September 4, 2026

The KOSDAQ opened at 802.32 points on September 4, 2026, recorded an intraday high of 816.54 points and an intraday low of 798.97 points, and closed at 813.50 points. Its +2.95% gain from the previous trading day was larger than the KOSPI’s +1.64% gain on the same trading day. This shows the relative closing moves of the two indexes, but the simultaneous movement on one day alone cannot identify the reason for either market’s advance. KOSDAQ closing data for September 4, 2026

SK Square Posts the Largest Gain Among Tracked Stocks

SK Square closed at 1,041,000 won on September 4, 2026, up 60,000 won(+6.12%) from the previous trading day. It recorded an opening price of 985,000 won, an intraday high of 1,049,000 won, an intraday low of 978,000 won, and trading volume of 575,921 shares. Although both the KOSPI and KOSDAQ rose on the same trading day, SK Square’s +6.12% was a larger closing move than the gains of both indexes. Prior analysis is available through SK Square closing data for September 4, 2026 and the SK Square stock hub.

SK hynix rose 51,000 won(+3.20%) from the previous trading day to 1,647,000 won on September 4, 2026. It recorded an opening price of 1,615,000 won, an intraday high of 1,683,000 won, an intraday low of 1,603,000 won, and trading volume of 3,996,430 shares. Based on the September 4, 2026 close, its +3.20% gain exceeded both the KOSPI’s +1.64% and the KOSDAQ’s +2.95%, but the simultaneous closing gains alone cannot establish a causal relationship between the indexes and the individual stock. See SK hynix closing data for September 4, 2026 and the SK hynix stock hub.

Samsung Electronics closed at 255,500 won on September 4, 2026, up 5,500 won(+2.20%) from the previous trading day. Its opening price and intraday low were each 251,000 won, its intraday high was 259,000 won, and its trading volume was 20,203,955 shares. Its closing gain on September 4, 2026, was higher than the KOSPI’s but lower than the KOSDAQ’s. Historical closing trends are available through Samsung Electronics closing data for September 4, 2026 and the Samsung Electronics stock hub.

Hyundai Motor Closes Unchanged Despite Index Strength

Hyundai Motor closed unchanged at 383,500 won on September 4, 2026, with a change of 0 won(0.00%) from the previous trading day. It recorded an opening price of 385,000 won, an intraday high of 393,500 won, an intraday low of 381,000 won, and trading volume of 633,482 shares. In contrast to the KOSPI’s +1.64% and the KOSDAQ’s +2.95% gains on the same day, Hyundai Motor’s closing price was unchanged. This shows that the indexes rose while Hyundai Motor was flat; these movements alone cannot determine the background behind the stock’s close. Individual-stock analysis is available through Hyundai Motor closing data for September 4, 2026 and the Hyundai Motor stock hub.

Separating Investor-Flow Figures From Reported Interpretations

The collected September 4, 2026, investor-category net trading figures were −37,231억원 for individual investors, +4,798억원 for foreign investors, and +16,692억원 for institutional investors. On the same trading day, the KOSPI moved +107.73 points(+1.64%) and the KOSDAQ moved +23.29 points(+2.95%). However, the fact that investor-category net trading and index closing figures were compiled on the same date alone does not support a conclusion that trading by a particular group directly caused the closing direction of an index or individual stock. Investor-flow data for September 4, 2026

A Korea Economic Daily report on the day’s market movement cited easing concerns about U.S. interest-rate hikes as the backdrop for the KOSPI’s gain of more than 1%. A MoneyToday report interpreted buying by foreign and institutional investors as driving the KOSPI’s advance. These are intraday and same-day market interpretations included in the respective articles; the September 4, 2026, regular-session closing data alone do not establish such causal relationships. Korea Economic Daily article MoneyToday article

Three Items to Check in the Next Regular Session

  • For the KOSPI, the September 4, 2026, close of 6,687.21 points and intraday high of 6,746.14 points, and for the KOSDAQ, the close of 813.50 points and intraday high of 816.54 points, can be used to compare the position of the next regular-session close.

  • For tracked stocks, the September 4, 2026, closing changes of SK Square +6.12%, SK hynix +3.20%, Samsung Electronics +2.20%, and Hyundai Motor 0.00% can be compared with index movements in the next regular session.

  • Investor-category net trading figures of −37,231억원 for individual investors, +4,798억원 for foreign investors, and +16,692억원 for institutional investors on September 4, 2026, can be compared with the next regular-session tally. Investor flows and closing prices can be viewed together, while avoiding the assumption that simultaneous changes on a single trading day establish causation.