Amid unfavorable factors such as a rebound in U.S. Treasury yields, concerns over a slowdown in global consumption, and Middle East tensions, the dominance of Samsung Electronics and SK Hynix stood out in the domestic stock market on the 21st.

This was the result of expectations for massive shareholder returns and price attractiveness driven by recent corrections.

In contrast, non-semiconductor sectors generally declined, and the Kosdaq, which once plummeted by more than 5%, barely managed to defend the 800 threshold by the end of the session.

According to the Korea Exchange and financial information service provider Yonhap Infomax, the Kospi closed up 60.37 points (0.88%) from the previous session at 6,912.95.

The index opened down 92.63 points (1.35%) at 6,759.95 and briefly slumped to 6,742.44 (-1.61%), but managed to recover its losses and successfully turn upward. While most sectors declined, large-cap semiconductor stocks and related issues, including Samsung Electronics and SK Hynix, rose across the board.

On this day, Samsung Electronics and SK Hynix closed up 3.87% and 2.31%, respectively, at 281,500 won and 1.73 million won.

Samsung Electronics preferred shares (+8.26%) and SK (+3.17%) also saw their stock prices rise compared to the previous day's close.

Notably, SK Securities, which was entrusted with brokerage for SK Hynix's 40 trillion won treasury stock purchase and retirement, showed a strong gain in the 5% range.

Meanwhile, SK Square (0.00%) finished trading at the exact same price as the previous day's close.

This upward trend in domestic semiconductors continued even though the three major New York stock indices fell simultaneously overnight due to concerns over slowing U.S. consumption driven by rebounding U.S. Treasury yields and Walmart's sluggish earnings.

The Dow Jones Industrial Average and the S&P 500 index fell 1.32% and 0.87%, respectively, while the Nasdaq index dropped 1.00%.

The day after the U.S. Department of the Treasury announced plans to expand the size of long-term Treasury buybacks, yields that had temporarily eased returned to an upward trend in just one day.

The yield on the benchmark 10-year U.S. Treasury note rose 5 bps (1 bp = 0.01 percentage point) to 4.70%.

Amidst these developments, Walmart's U.S. same-store sales for the second quarter recorded their lowest growth rate in six years, and October delivery Brent crude futures surged 2.36% from the previous session to $93.78 per barrel.

While major semiconductor stocks such as Micron (+3.97%) and SanDisk (+2.02%), along with SK Hynix American Depositary Receipts (ADRs) (+4.43%), rose, analysts noted that it was also influenced by the previous day's surge in domestic stock markets, where Samsung Electronics and SK Hynix soared 9.49% and 12.73%, respectively.

Nevertheless, commenting on the continued strength of domestic large-cap semiconductor stocks, Kim Seok-hwan, a researcher at Mirae Asset Securities, assessed it as "the power of shareholder returns."

He stated, "Following SK Hynix's announcement of shareholder returns in the 40 trillion won range, expectations for Samsung Electronics' special dividend in the 100 trillion won range have emerged, driving the strength of related stocks."

Kim Ki-baek, a researcher at Shinhan Securities, said, "The fact that South Korea's exports from August 1 to 20 increased by 56% compared to the previous year, with semiconductor exports in particular surging by 199%, also had an impact."

This is because the growth rate appears to have expanded further considering that semiconductor exports for the first 10 days of the month were tallied at $10 billion, surging 155% year-on-year.

Boosted by this, the Kospi electrical and electronic sector index closed up 1.96% from the previous session at 112,518.54.

Insurance (6.55%), telecommunications (3.38%), and retail (2.72%) also saw some gains, but most other sectors declined, including medical/precision equipment (-5.42%), construction (-5.36%), metals (-4.05%), machinery/equipment (-3.85%), transportation equipment/parts (-3.08%), securities (-2.45%), and entertainment/culture (-2.12%).

In particular, the Kosdaq index plunged 38.95 points (4.63%) to close at 801.94.

The Kosdaq opened down 16.84 points (2.00%) at 824.05 and continuously widened its losses, tumbling at one point to 795.57 (-5.39%).

It was the first time in 9 trading sessions that the Kosdaq index fell below the 800 mark during intraday trading.

Consequently, at around 10:05 AM, a sell sidecar was triggered due to fluctuations in Kosdaq 150 futures prices and the spot index, suspending the effectiveness of program purchase orders for 5 minutes.

Researcher Kim Ki-baek noted, "Selling pressure concentrated mainly on large-cap stocks due to intensifying discount rate burdens stemming from the resurgence of interest rate concerns. Most stocks within the top 20 by market capitalization declined, and some rotation was observed in K-beauty stocks such as Silicone II (+3.70%), which have earnings momentum."

Foreigners and institutional investors net sold 287.5 billion won and 346.5 billion won, respectively, pulling down the index.

Individual investors net bought 623.6 billion won.

After the Kosdaq hit its previous yearly high (1,229.42 on April 27) and turned downward, foreigners net bought a total of 4.5074 trillion won in the Kosdaq market from May to July, but have net sold 2.2716 trillion won so far this month.

On this day, foreigners also recorded a selling excess of 170.8 billion won in the main bourse, but net bought 228.3 billion won in the Kospi electrical and electronic sector, which includes Samsung Electronics and SK Hynix.

Foreigners net bought 439.4 billion won in Samsung Electronics and 14.4 billion won in SK Hynix.

Meanwhile, the Kospi 200 Volatility Index (VKOSPI), referred to as the Korean fear gauge, closed up 1.34% from the previous session at 58.03.

(Photo: Yonhap News)