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South Korea's Kospi Dips Despite Foreign and Institutional Buying as Retail Investors Drive Sell-Off

The South Korean Kospi index experienced a slight decline on October 18, with selling pressure from retail investors countering the positive influence of foreign and institutional purchases. According to the Korea Exchange, the Kospi dropped 4.22 points, or 0.13%, to close at 3,188.07.

Despite opening strong and temporarily crossing the 3,200 threshold, the index reversed gains during the session as retail investors locked in profits. Starting at 3,200.44—an increase of 8.15 points from the previous close of 3,192.29—the index gradually retreated amid profit-taking activity, dragging the market into negative territory by the end of the day.

Foreign investors and institutions provided some support in the main bourse, collectively purchasing equities valued at 189.6 billion won and 61.8 billion won, respectively. However, retail investors were significant net sellers, unloading shares worth 340.7 billion won, which ultimately weighed heavily on the index's performance.

Sector Breakdown

Sector-wise, insurance and retail stocks were among the worst performers, both dropping more than 2%. Additional weakness was apparent in securities, food and beverages, textiles and apparel, pharmaceuticals, and financial sectors. Conversely, gains were recorded in machinery and equipment stocks, which advanced over 1%. Other bright spots included electrical and electronics, non-metals, manufacturing, real estate, and construction industries, all showing modest improvements throughout the session.

Mixed Results for Major Stocks

Kospi’s blue-chip stocks displayed a mixed performance. Samsung C&T led the declines, tumbling more than 5%, followed by Samsung Biologics, Shinhan Financial Group, and KB Financial Group, all of which fell over 1%. Other prominent losers included Naver, Kia, SK Hynix, and Celltrion.

On the upside, Doosan Enerbility rose more than 2%, supported by robust buying demand. LG Energy Solution and HD Hyundai Heavy Industries also climbed over 1%, providing some relief to the index. Meanwhile, Samsung Electronics and Hyundai Motor managed to stay in positive territory, closing slightly higher after modest gains.

Kosdaq Climbs Higher

While the Kospi struggled, the secondary Kosdaq index closed on a positive note, inching up 2.40 points (0.29%) to settle at 820.67. After opening at 821.58, an increase of 3.31 points (0.40%) from the prior session's close of 818.27, the Kosdaq retained its upward momentum during early trading.

EcoPro BM was a standout performer, surging over 9%, while Rigaku Bio saw an impressive gain of more than 6%. Other contributors to the Kosdaq’s rise included EcoPro and Peptron, both advancing over 3%, as well as ABL Bio and Hugel, which climbed more than 1%.

Currency Market Update

In the Seoul foreign exchange market, the Korean won softened slightly against the US dollar. The won-dollar exchange rate rose by 0.4 won to end the day at 1,393.0 won, compared to the previous session’s close of 1,392.6 won.

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The Kospi’s decline highlights the dominant influence of retail trading sentiment on South Korea’s stock market, even amid foreign and institutional efforts to stabilize prices. Looking ahead, broader macroeconomic factors and domestic data will remain pivotal in shaping investor behavior and driving market trends.

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