SEOUL, May 21 (AJP) - South Korean stocks sharply outperformed regional peers Thursday, as Nvidia’s upbeat earnings and Samsung Electronics’ tentative labor deal triggered a powerful rally in Seoul’s chip-heavy market despite mixed trading across Asia.
The KOSPI jumped 606.64 points, or 8.42 percent, to finish at 7,815.59, dwarfing other gains across Asia. Japan’s Nikkei 225 rose more than 3 percent, while Chinese and Taiwanese shares lost ground, underscoring the strength of Korea’s rebound.
The daily point gain marked the largest on record, surpassing the previous record increase of 490.36 points set on March 5. It was also the first time since May 14 that the index closed above the 7,800 mark.
The index opened 3.85 percent higher at 7,486.37 and extended gains throughout the session, touching an intraday high of 7,819.23. The rapid rally triggered buy-side sidecar curbs in both the KOSPI and KOSDAQ markets in early trading, the first simultaneous activation in both markets since April 8.
The rebound was also supported by easing geopolitical concerns and a pullback in oil prices, after U.S. President Donald Trump said negotiations with Iran were in the “final stages,” raising hopes for a potential easing of Middle East tensions. U.S. Treasury yields also retreated overnight, helping restore risk appetite across global markets.
Investor sentiment was also supported by stronger-than-expected earnings from Nvidia, widely seen as a bellwether for global artificial intelligence demand. Nvidia reported its 12th consecutive quarter of record revenue, while adjusted earnings per share came in at $1.87, above Wall Street’s estimate of $1.76.
The results reinforced expectations that global AI infrastructure spending remains strong, lifting demand for Korean semiconductor shares tied to high-bandwidth memory and advanced AI chip supply chains.
Samsung Electronics’ tentative wage agreement with its labor union further fueled the rally, easing concerns over a possible strike at the country’s largest chipmaker. The deal came late Wednesday, shortly before a planned walkout was set to begin.
Institutional investors led the rally, buying 2.883 trillion won ($1.91 billion) worth of shares on the main bourse. Retail investors sold 2.647 trillion won, while foreign investors offloaded 233 billion won.
Most large-cap shares ended sharply higher. Samsung Electronics jumped 8.51 percent to close at 299,500 won after the tentative labor deal eased concerns over production disruptions. SK hynix surged more than 11 percent to 1,940,000 won, reflecting renewed optimism over AI memory demand.
SK Square also rallied, while Samsung Electronics preferred shares, Samsung Life Insurance and Samsung C&T gained strongly. Samsung Electro-Mechanics rose 13.48 percent, Samsung Life Insurance climbed 13.78 percent and Samsung C&T advanced 12.96 percent.
LG Electronics hit the daily upper limit, soaring 29.83 percent to 235,000 won, as investors priced in expectations for growth in its robotics and physical AI businesses.
Automakers also posted strong gains. Hyundai Motor jumped 12.50 percent to 666,600 won, while Hyundai Mobis surged 25.2 percent to 670,000 won on expectations that it could benefit from Hyundai Motor Group’s expansion into humanoid robots and physical AI.
The tech-heavy KOSDAQ also rebounded after four consecutive sessions of losses, rising 49.90 points, or 4.73 percent, to close at 1,105.97. Foreign investors and institutions bought 137 billion won and 139 billion won, respectively, while retail investors sold 258 billion won.
Semiconductor equipment and robotics shares led gains on the secondary market. Wonik IPS rose 11.97 percent, EO Technics climbed 18.8 percent and Rainbow Robotics advanced 16.5 percent.
By sector, electronics products led the gains with a 29.1 percent rise, followed by auto parts with 17 percent and display panels with 16.1 percent. Among themes, major IT shares climbed 14.6 percent, major automakers rose 13.7 percent and electric wire-related stocks gained 13.1 percent.
The dollar remained strong at 1,506.1 won after briefly retreating to the 1,490-won range earlier in the session.
Copyright ⓒ Aju Press All rights reserved.