On the 3rd in the dealing room at Hana Bank headquarters in Jung-gu, Seoul, a board shows the KOSPI index as it approached the 4,200 level after setting a new intraday all-time high. Kwon Do-hyun

The KOSPI surged more than 2%, surpassing the 4,200 mark intraday for the first time ever.

As of 11:51 a.m., the KOSPI was trading at 4,200.71, up 93.21 points (2.27%) from the previous session, setting a new intraday record. It cleared 4,200 just a week after topping 4,000 intraday and only three trading days after crossing 4,100.

On the main board, decliners outnumbered advancers, leaving the broader market subdued, but sharp gains in heavyweight stocks accelerated the index ascent. Starting the session at 4,123.36, up 15.86 points (0.39%) from the previous session, the KOSPI climbed to the 4,200 level on strength in key sectors including semiconductors, shipbuilding, defense, and power.

Among blue chips, Samsung Electronics (2.70%), SK hynix (8.05%), HD Hyundai Heavy Industries (4.57%), Hanwha Aerospace (6.03%), Naver (4.41%), HD Hyundai Electric (10.57%), and Hyosung Heavy Industries (11.8%) jumped more than 2%, lifting the index. Samsung Electronics rose intraday to 110,500 won, marking the first-ever ‘110K Electronics’, while SK hynix advanced to 606,000 won, reaching the ‘600K-nix’ milestone.

Optimism stemming from last week's Korea-U.S. summit and Korea-China summit, along with continued semiconductor strength, appears to be energizing large caps. The ruling party said it would push for separate taxation of dividend income, which is also contributing to the index rise.

Today, retail investors are leading the KOSPI. Individuals have net bought 308.6 billion won, while foreigners have net sold 352.4 billion won. Institutions have net bought 68.0 billion won.