[Edaily Reporter Lee Hye-ra] Foreign investors have posted the best investment performance among major market participants in the domestic stock market in June, a month marked by sharp volatility. This is attributed to their concentrated buying of defense, artificial intelligence (AI), and power-related stocks.

According to MP Doctor on the 16th, the average return on the top five stocks net purchased by foreign investors this month (1st–16th) was 11.55%. During the same period, institutions recorded a return of 2.78%, while individual investors recorded a loss of 2.10%.
During this period, foreign investors bought shares in the following order: #Samsung Electro-Mechanics, #Rino Industrial, #LS Electric, #LIG Defense & Aerospace, and #Kia. All five of the top net-purchased stocks rose in price. While LIG Defense & Aerospace and Samsung Electro-Mechanics drove the overall return, LIG Defense & Aerospace—the fourth-most purchased stock by foreign investors—posted a return of 33.10% during this period. Despite the growing possibility of peace talks between the U.S. and Iran, defense stocks surged across the board that day, benefiting from widespread expectations that South Korean defense companies would continue to benefit even after a peace agreement.
Foreign investors also boosted their returns by buying stocks related to power equipment and semiconductor components. Samsung Electro-Mechanics also posted a double-digit return of 10.76%. LS Electric rose 7.38%.
The average return for the top five stocks net-bought by institutional investors was 2.78%. The gap in returns compared to foreign investors was 8.7 percentage points; while institutions actively bet on expectations of expanded AI investment, performance varied by stock. It is analyzed that although they rode the wave of market-leading themes, increased volatility in related stocks prevented them from achieving results as expected.
The stock most heavily purchased by institutions during this period was #SK Square, which rose 15.84%. This is interpreted as reflecting the spotlight on the value of its stake in #SK Hynix and expectations for expanded AI infrastructure investment. Profits were also generated from #Samsung Electronics (4.05%) and #Hanmi Semiconductor (3.39%). On the other hand, losses were incurred in #NAVER (-7.96%) and #HPSP (-1.43%). NAVER showed short-term strength on expectations of AI cooperation following the visit of NVIDIA CEO Jensen Huang to South Korea, but subsequently turned weak as a large volume of profit-taking selling emerged amid volatility in the stock market.
Semiconductor equipment stocks also delivered disappointing results. While HPSP, Hanmi Semiconductor, and other equipment stocks had led the market in returns up until the previous day, they saw sharp declines on this day, causing investors to give back most of their gains.
Retail investors recorded a negative average return of -2.10% on the top five net-purchased stocks. Retail investors focused on the top market-cap stocks, buying Samsung Electronics, SK Hynix, #LG Electronics, #Hyundai Motor, and #Samsung Electronics Preferred. While Samsung Electronics, SK Hynix, and Samsung Electronics Preferred were all in positive territory, LG Electronics posted a return of -23.38% and Hyundai Motor recorded -4.80%, dragging down the overall performance.
These two stocks had also surged sharply during CEO Huang’s visit to South Korea, driven by expectations of collaboration in AI home appliances, data center cooling, autonomous driving, and robotics. However, as the KOSPI retreated following its record high, profit-taking selling pressure intensified, causing their stock prices to correct sharply.
The securities industry believes that a strategy focused on leading sectors where major players have been net buyers remains valid. Han Ji-young, an analyst at Kiwoom Securities, stated, “Even if a rotational trading pattern emerges, it is appropriate to maintain a strategy of increasing exposure to leading stocks in the AI value chain, such as semiconductors, based on earnings and narratives,” adding, “Existing leading sectors, such as defense and power equipment, are also expected to contribute to improving returns.”