(2nd LD) Seoul shares plunge over 5 pct on AI regulation concerns after U.S. midterms

South Korean stocks suffered a sharp fall after U.S. Democrats won both chambers of Congress. The KOSPI, the country’s benchmark share index, dropped 300 points, or 5.28 percent, to 5,383.80. The decline showed how strongly election expectations can affect overseas markets.

The main concern was possible regulation of artificial-intelligence data centers. Investors feared tighter rules could slow AI investment, hurting companies that supply chips, equipment, and related technology. The selling was especially severe among semiconductor-linked shares.

The won also weakened, reaching 1,342.1 per U.S. dollar at 3:30 p.m. It was down 0.6 won from the previous session’s close. Foreign investors sold 3.39 trillion won of shares, adding pressure to the market. The article gives no forecast for the currency, but continued policy concerns could keep technology shares sensitive.

The KOSPI stands for the Korea Composite Stock Price Index. It is South Korea’s benchmark stock index, meaning investors use it as a headline gauge of how the country’s listed shares are performing. A rise suggests broad gains, while a fall signals widespread weakness.

The index matters because it combines market movements across many companies rather than showing just one stock. In this session, the KOSPI dropped 300 points, or 5.28 percent, to 5,383.80. Semiconductor companies, including Samsung Electronics and SK hynix, suffered especially large declines.

That single closing figure helps summarize the day’s broad market shock. It does not explain every company’s performance, however. Hyundai Motor, Kia, and Naver rose even as the overall index fell. The KOSPI therefore measures the market’s general direction, while individual shares can move differently.

The sell-off was both large and broad. The KOSPI fell 300 points, or 5.28 percent, to 5,383.80. Losers outnumbered winners 534 to 344, showing that weakness extended well beyond a few major companies. The exchange even activated a sell-side sidecar, temporarily suspending program trading for five minutes.

Foreign investors sold a net 3.39 trillion won worth of shares. Institutions bought 841.8 billion won, while individuals bought 2.28 trillion won. Those purchases helped absorb some selling, but they did not prevent the index from plunging. Trading volume reached 256.8 million shares, worth 22.6 trillion won.

The foreign outflow mattered because it added direct selling pressure during a technology-led shock. Mirae Asset analyst Kim Seok-hwan linked the “blue wave” to weakness across semiconductor value chains and a foreign sell-off. The figures show a market-wide decline, not merely an isolated drop in chip stocks.

The article calls the Democrats’ landslide victory in the U.S. midterm elections a “blue wave.” Democrats gained control of both chambers of Congress, and the new Congress was due to take control in January. That changed investors’ expectations about future U.S. policy.

The concern centered on artificial-intelligence data centers. These facilities support the growing AI industry, so investors feared Congress could impose tighter regulations on them. The article does not specify the proposed rules. It reports that the possibility raised doubts about the pace of future AI investment.

Those doubts affected South Korean shares tied to the semiconductor value chain. Samsung Electronics fell 7.57 percent, SK hynix dropped 9.46 percent, and Hanmi Semiconductor declined 9.13 percent. Analyst Kim Seok-hwan said the blue wave dragged down semiconductor shares and encouraged foreign selling. The market reaction was therefore based on expected policy effects, not an already enacted rule.

AI data centers require large amounts of computing hardware, including semiconductors and specialized equipment. If regulation makes projects slower, more expensive, or harder to approve, companies may delay or reduce investment. That would weaken expected future orders throughout the technology supply chain.

The mechanism is simple: fewer or smaller data-center projects can mean less demand for chips, chipmaking tools, and electronic components. Investors value companies partly on expected future sales, so even a policy concern can push their share prices down before actual orders change. The article links this concern directly to semiconductor value chains.

South Korean examples show the market’s reaction. Samsung Electronics fell 7.57 percent, SK hynix plunged 9.46 percent, and Hanmi Semiconductor slumped 9.13 percent. The article does not report canceled projects or enacted restrictions. It describes an expectation that tighter rules could slow AI investment, with possible consequences for suppliers.

The day’s moves reflected different expectations for different industries. Semiconductor shares faced direct concern that tighter AI data-center rules could slow investment. Defense shares also weakened as hopes increased for diplomatic solutions to conflicts in the Middle East and East Europe.

The article gives clear examples. Samsung Electronics fell 7.57 percent, SK hynix dropped 9.46 percent, SK Innovation declined 7.68 percent, and Hanwha Aerospace lost 7.48 percent. By contrast, Hyundai Motor rose 3.53 percent, Kia gained 5.22 percent, and Naver jumped 8.26 percent.

The report does not identify a specific reason for the automobile and internet-platform gains. Therefore, the safest conclusion is that investors reassessed sectors unevenly after the election result. Technology suppliers faced a stated AI-investment concern, while defense stocks faced changing war expectations. The contrasting performance shows that one market shock can produce both winners and losers.

A bond generally promises fixed payments. When investors bid up its market price, those same payments represent a smaller return compared with the purchase price, so the yield falls. When the price drops, the fixed payments represent a larger return, so the yield rises. This creates the usual inverse relationship.

South Korea’s report showed that relationship clearly. Government bond prices closed higher, while the three-year Treasury yield fell 4.5 basis points to 3.669 percent. The yield on benchmark five-year government bonds also dropped 6.8 basis points to 3.769 percent. The price movement and yield movement pointed in opposite directions.

Higher prices generally indicate stronger investor demand for that debt, although the article does not identify every reason behind the demand. In this session, money appeared to move toward government bonds even as shares fell sharply. That contrast suggests investors sought the relative stability of government debt during the market sell-off.