South Korean stocks suffered an unusually sharp selloff on November 5 as investors reassessed the outlook for artificial intelligence investment after Democrats took control of the US Congress in the midterm elections. The Kospi closed at 5,383.80, down 300 points or 5.28 percent, while the Kosdaq fell 5.11 percent to 678.41. The decline became severe enough for the Korea Exchange to activate sell-side program trading curbs in both markets.
Foreign selling drove much of the pressure. Overseas investors sold a net 3.402 trillion won of Kospi shares even as domestic individuals and institutions bought on balance. Semiconductor heavyweights bore the brunt of the retreat: Samsung Electronics dropped 7.57 percent and SK Hynix lost 9.46 percent. Their declines amplified the damage to a market where large chipmakers carry substantial index weight.
Foreign selling concentrates the damage in chips
The market reaction reflected concern that a Democratic-controlled Congress could strengthen oversight of AI data centers or make construction permits more difficult. If tighter requirements delay new data centers, major technology companies may postpone some infrastructure spending. That would weaken or defer demand for high-bandwidth memory and other chips supplied by South Korean manufacturers. The available evidence establishes this as an investor concern rather than a confirmed reduction in orders or capital expenditure.
The contrast with Wall Street made South Korea’s fall more conspicuous. Over the comparable period, the Dow Jones Industrial Average rose 3.03 percent, the S&P 500 gained 1.58 percent and the Nasdaq advanced 1.44 percent. Japan’s Nikkei declined 1.79 percent, considerably less than the Korean benchmarks. US technology companies were supported by expectations that stricter rules could reduce their investment burden, while Korean suppliers were marked down because slower construction could reduce demand for their products.
The political change also introduces questions about existing US industrial incentives. South Korean semiconductor companies are monitoring whether tax credits for American factories and equipment will be extended, whether congressional scrutiny of subsidies will intensify, and whether restrictions on expanding production in China will change. These issues affect investment costs and operating flexibility, but the evidence does not show that Congress has already revised the relevant programs.
Policy effects diverge across Korean industries
The implications are less uniformly negative outside semiconductors. South Korean automakers do not expect the 15 percent tariff on Korean vehicles to fall immediately, but the restoration of support for cleaner vehicles or consumer electric vehicle tax credits could benefit Hyundai Motor, Kia and domestic battery suppliers. Such changes would require legislation and presidential approval, leaving their timing and final form uncertain.
Shipbuilding and defense may have greater policy continuity because rebuilding US shipyard capacity and strengthening naval power have support across party lines. South Korean companies with US shipyard investments or joint projects could remain positioned for contracts. Increased attention to electricity demand and energy security may also create opportunities for Korean power-equipment suppliers, although no specific new orders were identified in the supplied evidence.
Investors now face a divided picture rather than a single economy-wide verdict. Chip and power-equipment shares remain exposed to signals about data-center permitting and AI capital spending, while shipbuilding, defense, electric vehicles and batteries depend on separate legislative choices. The next indications will come from congressional proposals on AI infrastructure, subsidy oversight and tax incentives, together with any changes in spending plans or orders reported by US technology companies and Korean suppliers.