Foreigners sell KRW 3 trillion worth of KOSPI shares…retail investors absorbed it all

Foreigners sell more than KRW 2 trillion worth of Samsung Electronics

On the 26th, the KOSPI index sank more than 3%, tumbling into the 5,400 range. As foreign investors extended their net selling of KOSPI shares for a sixth consecutive session, retail investors stepped in with net buying of more than KRW 3 trillion.

Samsung Electronics down 4.71%, SK hynix plunges 6.23%

The KOSPI closed down 3.22% at 5,460.46. Losses were driven largely by sharp declines in Samsung Electronics and SK hynix—the No. 1 and No. 2 stocks by market cap—following shockwaves from Google’s “TurboQuant.”

Samsung Electronics ended the session down 4.71% at KRW 180,100, while SK hynix plunged 6.23% to close at KRW 933,000. Samsung Electronics preferred shares fell 5.46% to close at KRW 126,300. SK Square, known as a “proxy play on hynix” for holding about 20% of SK hynix, dropped 7.77% to KRW 558,000. As of that day, SK Square ranked sixth by market capitalization on the KOSPI.

These stocks slid as expectations spread that demand for memory semiconductors could come in below prior forecasts. Google Research released a paper on its AI algorithm “TurboQuant.” The key claim is that it has developed a technology that reduces LLM memory usage by up to six times versus existing levels without lowering answer accuracy.

If such an approach is realized, big tech firms could run AI services with less semiconductor infrastructure than previously expected.

Foreigners, following the previous day, continued trillion-won-scale net selling in Samsung Electronics. They net sold KRW 2.0408 trillion worth of Samsung Electronics alone. They also unloaded KRW 789.6 billion worth of SK hynix.

Intense battle over flows…foreigners sold, retail investors bought

The KOSPI saw a fierce tug-of-war over flows during the session. Around 12:30 p.m., bargain hunting by retail investors pushed the index back up to 5,521.72 at 12:30 p.m., but it gave up all gains amid persistent foreign selling. At 3:12 p.m., it slid to an intraday low of 5,448.12.

Foreigners posted net sales of KRW 3.0980 trillion on the KOSPI, sharply expanding the scale of selling from the previous day (KRW 1.2895 trillion). Foreign investors have extended net selling on the KOSPI for six consecutive sessions since the 19th. Cumulative net selling over the period totals about KRW 13 trillion.

Almost all of the shares dumped by foreigners were absorbed by retail investors. Individuals bought a net KRW 3.0598 trillion worth of KOSPI shares. Institutions net sold about KRW 339.0 billion.

The recent clear uptrend in the won-dollar exchange rate also appears to be adding to foreign flow pressure and amplifying volatility in the domestic stock market. The won-dollar exchange rate rose KRW 7.3 from the previous day to KRW 1,507.0. When the exchange rate rises sharply, concerns over FX losses on won-denominated assets tend to grow, often prompting foreign investors to cut their holdings of domestic stocks.

The KOSDAQ closed down 22.91 points (1.98%) from the previous day at 1,136.64. The pharmaceutical and biotech sector (+2.77%) helped partially cushion the index, with Alteogen (+6.28%), ABL Bio (+4.41%), and Kolon TissueGene (+17.11%) among notable gainers, posting a market contribution of +0.72%.

Foreigners also sold heavily in KOSDAQ shares. While individuals net bought KRW 485.1 billion, foreigners and institutions net sold KRW 301.6 billion and KRW 134.4 billion, respectively.

By Sun Hankyul always@hankyung.com