KOSPI ended June 5 down 5.54% at 8,160.59, while Samsung Electronics (005930.KS) fell 6.40% and SK Hynix (000660.KS) dropped 9.92%, according to CNBC market data. The move followed a Wall Street rotation out of AI-linked semiconductor shares.
Foreign investors sold a net KRW 6.95 trillion ($4.5B) on KOSPI June 4 — the second-largest daily foreign net sell on record — as KRW/USD breached 1,530 won for the first time since the global financial crisis. KOSPI fell 1.84% to 8,639.41; KOSDAQ rose 2.31%. Foreigners have net-sold for 19 consecutive sessions (~KRW 66T total).
South Korea's KOSPI closed at 7,812.49 on May 21, rising 8.37% in a session steep enough to trigger a buy-side circuit breaker. Samsung Electronics' resolution of a months-long performance-bonus dispute and Nvidia's better-than-expected Q1 FY2027 results catalyzed the rally simultaneously, reversing five consecutive sessions of losses that began with a sell-circuit near the 8,000 level on May 15.
Foreign investors sold a net ₩7.34 trillion from Korean equities on May 19, extending their streak to nine consecutive sessions of net selling and pushing total outflows past ₩48 trillion since May 7. The KOSPI fell 3.25% to 7,271.66 — intraday the index shed as much as 4.98% — dragged by semiconductor sector weakness after Micron ($MU) shed 5.95% and SanDisk ($SNDK) 5.3% in New York overnight. Hyundai Motor (005380.KS) led large-cap declines with an 8.9% drop.
US 30-year Treasury yields hit 5.11%, clearing the psychologically key 5% level, while the 10-year note reached 4.6% intraday before settling near 4.577%. The S&P 500 fell 1.24% to 7,408.50 as technology stocks led declines — Nvidia $NVDA off 4.42%, Intel $INTC down 6.18%. Deutsche Bank flagged the post-earnings lull and Middle East tensions as catalysts for defensive positioning.
KOSPI 200 futures plunged 5.13% to 1,112.46 at 09:19 KST on May 18, triggering the sell-side sidecar for the second consecutive session. The KOSPI cash index recovered from an intraday low of -4.7% to close at 7,516.04 (+0.31%), as domestic retail buyers absorbed over KRW 2.5 trillion in foreign selling. The USD/KRW rate crossed 1,502, re-breaching the 1,500 level, with foreign investors recording eight straight days of net selling totaling over KRW 4 trillion.
South Korea's Prime Minister Kim Min-seok issued a public ultimatum May 17, warning that May 18 talks at the Central Labor Relations Committee are 'the last chance' to avert a general strike by 50,000 Samsung Electronics workers scheduled for May 21. Samsung shares slid roughly 8% on strike risk, with the dispute centered on a stark bonus gap: 607% of annual salary for the memory unit versus 50–100% for foundry and System LSI workers.
Margin lending in Korean equity markets reached a record KRW 36.47 trillion as of May 15, up 33.66% from year-end 2025, as retail investors borrowed heavily to chase the KOSPI's approximately 70% year-to-date gain. Short-selling balances simultaneously surged 67.18% to KRW 20.58 trillion, near an all-time peak, prompting securities firms to warn of potential cascading forced-liquidation events.
South Korea's KOSPI crossed 8,000 for the first time in history on May 15, peaking at 8,046.78 before a circuit breaker was triggered as KOSPI 200 futures fell more than 5%. The index closed at 7,493.18, down 6.12%, as foreign investors dumped a net KRW 5 trillion in a single session. Retail investors' seven-day, KRW 30-trillion buying streak could not offset the outflow, while KB Securities raised its KOSPI target from 7,500 to 10,500.
South Korea's KOSPI closed at a record 7,981.41 on May 14, its second consecutive all-time high, bringing the 8,000-point threshold within 0.24%. Samsung Electronics and SK Hynix led the rally as Nvidia's H200 China export authorization spotlighted Korean HBM suppliers as direct beneficiaries; the National Pension Service added roughly ₩50 trillion (~$36 billion) in two weeks.
South Korea's KOSPI closed at a record 7,844.01 (+2.63%) on May 13, led by Hyundai Motor (005380.KS) surging 9.91% to KRW 710,000 on robotics revaluation, with Hyundai Mobis up 18.43%. SK Hynix (000660.KS) gained 7.68% to KRW 1,976,000 as AI server investment expectations revived following Jensen Huang's reported China trip. Domestic investors net-bought KRW 3.57 trillion, absorbing KRW 4 trillion in foreign selling.
South Korea's KOSPI closed at a record 7,822.24 on May 11, adding 324 points (+4.32%) as semiconductor stocks repriced after the Philadelphia Semiconductor Index surged 5.51% on May 8. SK Hynix cleared 190,000 KRW (+11%) and Samsung Electronics crossed 280,000 KRW (+6%), putting the 8,000 level within 2.2% reach.