"Why Is My Account the Only One in the Red?" Samsung Electronics and SK hynix Account for Half of KOSPI Market Cap

\r\n
[Financial News] KOSPI (Korea Composite Stock Price Index) continued its upward run, briefly breaking above the 8,400 level during intraday trading. However, the combined market capitalization of Samsung Electronics and SK hynix has for the first time surpassed half of the entire KOSPI, highlighting a deepening divide among stocks.
Market watchers also expect the concentration in large-cap stocks to intensify further as single-stock leveraged exchange-traded funds (ETFs) tied to the two companies are launched.
According to Korea Exchange (KRX) on the 28th, the previous day the KOSPI index surged as much as 5.08% intraday to 8,457.09, briefly testing the 8,500 level. Six minutes after the market opened, a buy-side circuit breaker was triggered on the KOSPI market, suspending program buy orders for five minutes. It was the 10th buy-side circuit breaker this year and the first in four trading days since the 21st.
\r\n
\r\n\r\n
As intraday volatility widened, the market’s underlying polarization became even more pronounced despite the index’s gains. Only 77 KOSPI stocks rose, while 826 declined, meaning the number of losers was more than 10 times the number of gainers.
At the center of this market concentration are Samsung Electronics and SK hynix. Their combined market capitalization stands at 3,394 trillion won, and as their share prices climbed to as high as 300,000 won for Samsung Electronics and 2.24 million won for SK hynix, they came to represent 50.44% of the entire KOSPI, worth 6,728 trillion won. That is more than double the 23.1% share recorded in April last year, when KOSPI had fallen to the 2,200 level after the U.S. reciprocal tariffs took effect. The launch of 16 leveraged ETFs on the day, each tracking twice the daily price movement of the two stocks, also helped draw in market funds.
The strength in the semiconductor sector was supported by gains in U.S. markets. On Wall Street, Micron jumped 19.3% after UBS sharply raised its target price by three times. Related names such as SanDisk, which rose 7.5%, also advanced. In the domestic market, SK Square, a top market-cap stock, gained 8.04%, while Samsung Electro-Mechanics rose 3.69%. Samsung SDS hit the daily upper limit, emerging as a beneficiary of expanding artificial intelligence infrastructure.
\r\n
\r\n\r\n
Outside semiconductors, however, most other sectors were weak. In the power equipment segment, LS ELECTRIC Co., Ltd. (-8.25%), HD Hyundai Electric Co., Ltd. (-4.7%), and Taihan Cable & Solution Co., Ltd. (-7.04%) all closed lower. Construction stocks also fell across the board on profit-taking, with Hyundai Engineering and Construction (-5.53%), Daewoo Engineering & Construction Co., Ltd. (-9.17%), Samsung E&A (-6.04%), and GS Engineering & Construction (-7.06%) all declining.
Against this backdrop, the market is warning that a so-called 'FOMO rally' has taken hold, with buying concentrated after KOSPI broke above the 7,000 level. That has raised concerns about overheating and about excessive polarization driven by the rush into leading stocks. There are also fears that the growing number of single-stock leveraged ETFs could increase market volatility, especially in the semiconductor sector.
\r\n
\r\n\r\n
With the combined market cap of Samsung Electronics and SK hynix accounting for half of KOSPI, a rapid expansion in these single-stock leveraged products could make the market as a whole more uncertain even on small price moves in the two stocks. On the day, trading volume in the 16 leveraged ETFs totaled 10.4071 trillion won.
The KOSPI 200 Volatility Index, which measures market volatility, closed at 70.83, up 4.02% from the previous session, a level similar to the period immediately after the outbreak of the Iran war. Foreign investors extended their net selling streak to 14 consecutive trading days, offloading 564.4 billion won on the Korea Exchange Main Board.
Meanwhile, even as concerns grow over a possible correction after the recent sharp rally, securities firms are continuing to raise their upper-end forecasts for the KOSPI. Samsung Securities lifted its year-end KOSPI target for this year from 8,400 to 11,000, an increase of about 30%.
\r\n
\r\n
hsg@fnnews.com Han Seung-gon Reporter