KOSPI edges higher after volatile session as tech stocks drive gains

A trading board shows KOSPI in the dealing room of Hana Bank’s headquarters in Seoul, Tuesday. The benchmark index closed at 8,476.48, up 81.83 points, or 0.97 percent, from the previous session. Yonhap

KOSPI ended slightly higher on Tuesday after opening on a positive note, supported by a strong overnight rally in U.S. technology shares, but overall trading was marked by fluctuations.

The index began the session up 22.05 points, or 0.26 percent, at 8,416.70, and briefly built on early momentum. However, it soon drifted into a narrow range as fluctuations persisted throughout the day before closing at 8,476.48, up 81.83 points, or 0.97 percent, from the previous session.

Persistent foreign selling acted as a drag on broader upside momentum.

In the United States, equities finished higher as a rebound in mega-cap tech stocks helped reverse recent weakness tied to valuation concerns. The Dow Jones Industrial Average climbed 0.59 percent, breaking above the 52,000 mark for the first time. The S&P 500 rose 1.18 percent, while the Nasdaq Composite advanced 2.07 percent.

Semiconductor names led the advance, with Nvidia, Micron Technology and Broadcom fueling a 3.83 percent gain in the Philadelphia Semiconductor Index.

Those positive moves provided some support for Korean chipmakers, though gains were uneven due to continued foreign outflows.

Samsung Electronics and SK hynix rose 3.41 percent and 0.84 percent, respectively. SK Square, the largest shareholder of SK hynix, also ended higher, up 3.48 percent.

Analysts noted that volatility in the domestic equity market has been amplified by concentrated flows into single-stock leveraged exchange-traded funds (ETFs) tied to Samsung Electronics and SK hynix, which have intensified intraday distortions and exaggerated index moves.

Sentiment was further pressured by renewed geopolitical jitters after reports of fresh U.S.-Iran tensions over the weekend.

“Uncertainty has also stemmed from global tech pricing signals, including reports of potential Apple price increases,” said Han Ji-young, an analyst at Kiwoom Securities.

Concerns have centered on the possibility that hyperscalers could curtail investments if memory chip costs rise further, raising questions about the durability of semiconductor demand.

Given the outsized weight of Samsung Electronics and SK hynix in Korea’s benchmark index, swings in the two stocks continue to act as a key driver of broader market volatility.

The secondary Kosdaq, meanwhile, opened higher, gaining 4.64 points, or 0.50 percent, to 925.21, but quickly reversed direction during intraday trading, at one point slipping into the 910 range. It eventually closed at 916.18, down 4.39 points, or 0.48 percent.

The index had jumped 8 percent in the previous session, reclaiming the 900 level for the first time in three days, as expectations grew around potential market-support policies marking the 30th anniversary of the junior bourse.

In Seoul’s foreign exchange market, the won opened at 1,543.1 per U.S. dollar, up 2.1 won from the previous session, but later reversed course to close onshore trading at 1,549.4 per dollar, down 4.2 won.