[Edaily Reporter Kim Hyung-il ] The KOSPI and KOSDAQ both closed with gains in the 4% range. This was driven by strong buying momentum—particularly in semiconductor stocks—on the New York Stock Exchange overnight, coupled with improved investor sentiment following a drop in international oil prices. Early in the session, the sharp rally triggered buy-side circuit breakers in both markets; although the indices later gave up some of their gains, they continued their rebound as bargain-hunting buying—centered on large-cap stocks like semiconductors and secondary batteries that had suffered significant declines—flowed into the market.

According to MP Doctor on the 10th, the KOSPI closed at 5,239.13, up 220.28 points (4.39%) from the previous trading day. The KOSDAQ closed at 667.61, up 28.64 points (4.48%). Both major indices managed to rebound for the first time in four trading days.

On that day, the KOSPI opened at 5,247.22, up 228.37 points (4.55%) from the previous trading day, while the KOSDAQ opened at 661.73, up 22.78 points (3.56%). As the upward trend continued early in the session, the KOSPI climbed as high as 5,300.92 during the session, marking a 5.62% gain, while the KOSDAQ also surged to 671.91, recording a 5.16% increase. However, profit-taking emerged in the afternoon, causing the gains to narrow somewhat.

Due to the sharp rally in early trading, buy-side circuit breakers were triggered one after another in both the KOSPI and KOSDAQ markets. According to the Korea Exchange, a buy-side circuit breaker was triggered in the KOSPI market at 9:06 a.m. At the time of activation, the price of the nearest-month Mini KOSPI 200 futures contract stood at 821.04 points, up 5.76% from the reference price of 776.26 points. As this rate of increase persisted for one minute, buy orders from program trading were suspended for five minutes. At the time of activation, net program buying amounted to 79.3 billion won.

At 9:10 a.m., a buy sidecar was also triggered in the KOSDAQ market. At that time, the KOSDAQ 150 futures were up 6.29% at 1,099.50, and the KOSDAQ 150 spot index rose 5.87% to 1,095.53. Consequently, the validity of buy orders in program trading was suspended for five minutes in the KOSDAQ market as well.

A buy-side car is a market stabilization measure that suspends the effectiveness of buy orders from program trading for five minutes when the futures price remains above a certain level for one minute. It is triggered when KOSPI 200 futures rise more than 5% above the reference price for one minute, or when KOSDAQ 150 futures rise more than 6% and the spot index rises more than 3% from the previous trading day’s closing price—each condition must persist for one minute.

By stock, large-cap stocks, including semiconductor stocks, led the index rebound. Among the top KOSPI stocks by market capitalization, SamsungElectronics(005930)closed at 198,900 won, up 4.74% from the previous trading day, while SK hynix(000660)closed at 1,212,000 won, up 6.69%. SamsungElectronics(1P)(005935)(5.37%), SKSQUARE(402340)(5.26%), SamsungElectroMechanics(009150)(4.63%), and LG Energy Solution(373220)(3.93%) also posted gains. In contrast, SAMSUNG BIOLOGICS(207940)fell 2.78%.

The recovery led by large-cap stocks was also notable. The KOSPI Large-Cap Index rose 4.53%, outperforming the gains of mid-cap (3.14%) and small-cap (2.43%) stocks. By sector, medical and precision instruments rose 8.53%, recording the highest gain, followed by machinery and equipment (7.65%), construction (7.15%), electrical and electronics (5.73%), and manufacturing (4.91%).

On the KOSDAQ market, semiconductor and equipment stocks, as well as secondary battery stocks, also performed strongly. Among the top market-cap stocks, EO Technics Co., Ltd.(039030)surged 14.48%, while ECOPRO CO., LTD(086520)(10.23%), ECOPRO BM CO., LTD.(247540)(8.70%), JUSUNG ENGINEERING Co.,Ltd.(036930)(7.48%), and Rainbow Robotics(277810)(7.44%) also rose sharply. Alteogen Inc.(196170)rose 4.69%, and SIMMTECH Co., Ltd.(222800)rose 6.71%. HLB INC.(028300)rose only 0.33%. By sector, financials posted the highest gain, rising 6.79%, followed by machinery and equipment (6.31%), non-metals (6.10%), and electrical and electronics (5.88%).

In terms of supply and demand, foreign investors and institutions both engaged in net buying on the KOSPI market. Foreign investors and institutions made net purchases of 668.3 billion won and 716.9 billion won, respectively, while retail investors made net sales of 1.8362 trillion won. Notably, foreign investors returned to net buying on the KOSPI market for the first time in eight trading days. On the KOSDAQ market, institutions were net buyers of 223.1 billion won, while foreign investors and retail investors were net sellers of 123.6 billion won and 94.6 billion won, respectively.

At the individual stock level, performance varied depending on earnings and sector-specific factors. NHN(181710)hit the daily price limit after reporting that its third-quarter operating profit reached 58.8 billion won—a 112.6% increase year-over-year—marking its highest quarterly profit on record. Airline stocks also performed strongly as expectations of benefits from falling international oil prices came into focus. KoreanAirLines(003490)surged by over 11%, driven by expectations of synergies from its merger with Asiana Airlines(020560).

The rebound in the domestic stock market that day was driven by the strength of semiconductor stocks in the U.S. market overnight and the decline in international oil prices. On the 9th (local time), the Dow Jones Industrial Average closed at 52,389.75 on the New York Stock Exchange, up 2.15% from the previous trading day. The S&P 500 Index rose 2.35%, and the Nasdaq Index rose 2.74%. In particular, the Philadelphia Semiconductor Index surged 6.9%. Buying momentum spread across the semiconductor sector, with AMD rising 13.3% and Broadcom gaining 8.8%. In contrast, Nvidia fell 4.3% amid ongoing controversy, including the launch of an independent investigation by its board of directors.

Falling international oil prices also supported risk-on sentiment. West Texas Intermediate (WTI) crude oil fell by more than 4% to below $87 per barrel, as U.S. President Donald Trump downplayed the need for further attacks on Iran and reports emerged regarding discussions to unfreeze Iranian funds. The Volatility Index (VIX) fell to 19.9 points, and the Fear & Greed Index stood at 32 points, indicating a partial recovery in risk appetite.

Lim Jeong-eun, an analyst at KB Securities, noted, “As bargain-hunting entered the U.S. stock market and international oil prices plummeted following President Trump’s remarks downplaying the need for further attacks on Iran, a strong rebound emerged, particularly in semiconductor stocks.” She added, “In the domestic stock market as well, improved investor sentiment led to a rebound across all sectors, with the proportion of rising stocks reaching the 70% range on both the KOSPI and KOSDAQ.”

She continued, “The recovery spread primarily among large-cap stocks that had suffered significant declines, such as machinery and equipment, construction, secondary batteries, and semiconductors, and foreign investors turned to net buying on the KOSPI for the first time in eight trading days.” She explained, “Airlines performed strongly amid falling international oil prices, and KoreanAirLines rose sharply, bolstered by expectations of synergies from its merger with Asiana Airlines.”

Researcher Lim added, “The U.S. Consumer Price Index (CPI) for October, to be released today, is a key indicator for gauging whether inflation concerns are easing following yesterday’s drop in oil prices,” noting, “Market attention will be focused on this release.”