KOSPI Closes at 3,395.54, Setting Record High for Third Consecutive Day

KOSDAQ Closes Up 1.48% at 847.08

The KOSPI continues to make history day after day. Driven by net buying from foreign and institutional investors, it set new record highs for three consecutive days.

On September 12, the KOSPI closed at 3,395.54, up 51.3 points (1.54%) from the previous trading session. This marked a significant leap from the previous all-time closing high of 3,344.20 set the day before, bringing the index to the verge of surpassing the 3,400 mark.

On the 12th, when the KOSPI index started the day by recording an all-time high for the third consecutive day, the KOSPI, exchange rate, and KOSDAQ indices were displayed on the index board in the Hana Bank dealing room in Jung-gu, Seoul. 2025.09.12 Photo by Dongju Yoon

Foreign investors alone recorded a net purchase of 1.4192 trillion won in the KOSPI market on this day, surpassing the previous record of 1.3931 trillion won set on September 10. Institutional investors also contributed to the upward trend, with net purchases exceeding 600 billion won in the KOSPI market during the day. In contrast, individual investors sold more than 2 trillion won worth of shares on their own.

The rise in the KOSPI was attributed to two main factors: the policy stance of President Lee Jaemyung to ease capital gains tax criteria for stocks announced the previous day, and growing pressure for a U.S. base rate cut.

The share prices of Samsung Electronics and SK Hynix, the two largest companies by market capitalization, both posted significant gains. Samsung Electronics closed at 75,400 won, up 2,000 won (2.72%) from the previous session, reaching a new 52-week high.

SK Hynix saw an even larger increase. Its share price rose by 21,500 won (7.00%) to close at 328,500 won, setting another all-time high for the second consecutive day. This surge was fueled by news that SK Hynix had established the world's first mass production system for fourth-generation high-bandwidth memory (HBM).

Other top market cap stocks, excluding Samsung Electronics and SK Hynix, showed mixed performance. HD Hyundai Heavy Industries fell by 1.35%, while Hanwha Aerospace, Kia, and Celltrion each closed down by less than 1%.

Experts predict that the KOSPI's upward momentum will continue through the end of the year. Kim Byoungyeon, a researcher at NH Investment & Securities, stated, "Although there are concerns about the government's stance, considering structural goals, it is highly likely that the year-end index will finish above the all-time high rather than below 3,000." He added, "In Korea, as in the United States, liquidity expansion will become a major issue, and sector rotation is expected to continue within policy-related stocks."

The KOSDAQ also closed up 1.48% from the previous day at 847.08.

Among the top KOSDAQ stocks by market capitalization, Alteogen (up 3.91%), Ecopro BM (up 1.80%), Ecopro (up 1.03%), and Rainbow Robotics (up 1.90%) showed gains. However, Peptron (down 1.29%), PharmaResearch (down 1.38%), and ABL Bio (down 0.09%) declined.

With both foreign net buying and expectations of a U.S. rate cut, the won-dollar exchange rate remained stable. In the Seoul foreign exchange market, the won-dollar rate closed at 1,388.2 won per dollar, down 3.6 won from the previous day.