Seoul’s two markets went opposite ways: KOSPI recovered from a 1.35% opening drop to close up 0.88%, while KOSDAQ fell 4.63% and tripped its 32nd sidecar trading curb of 2026 as rising US yields hammered growth stocks.
A 2x daily-reset product does not double your holding-period return: after a +10% then -10% two-day swing, the underlying is down 1% but the 2x product is down 4%. Here is the reset mechanism, the decay math on volatile Korean names like Samsung Electronics and SK Hynix, and the FSC/KRX rules that govern these products.
The KOSPI jumped 5.89% to 6,852.58 after SK Hynix unveiled a record 40 trillion won buyback-and-cancellation plan. Foreign investors bought 1.7 trillion won of Seoul shares while the won hit its strongest level against the dollar in about 11 months.
Korea’s KOSPI closed down 5.80% at 6,471.17 after a US Treasury yield spike and a global semiconductor rout hit Samsung Electronics and SK Hynix. A sell-side sidecar fired at the open, retail investors bought the dip, and the won broke below 1,400.
The KOSPI surged past 7,200 intraday on a semiconductor rally, then an afternoon wave of profit-taking erased the entire gain, closing down 1.55% at 6,869.83. Foreign investors kept buying while locals sold, and the collapse of the US-Iran ceasefire added a fresh layer of risk.
The Bank of Korea Base Rate reaches Korean stocks through six channels: the won, foreign flows, valuations, bank margins, exporters, and retail leverage. As of August 2026, margin lending stood near 30.9 trillion won against 100.1 trillion won of investor deposits — here is how to read both around a rate decision.
The KOSPI rose 2.42% to 6,977.94 — a fifth straight gain — after briefly crossing 7,000. Foreign investors bought roughly 1.45 trillion won of KOSPI shares, concentrated in Samsung Electronics and SK Hynix, while soft US inflation data supported risk appetite.
KRX publishes daily net-buying figures for foreigners, institutions, and individuals on data.krx.co.kr and Naver Finance; the on-screen tables are typically labeled in millions of won, while Korean flow headlines quote units of 100 million won. The key skill: split “institutions” into pension, financial-investment, and trust money before drawing any conclusion, because each behaves differently.
The KOSPI closed at 6,813.34, up 3.56% for a fourth straight gain, as an in-line US CPI print and shareholder-return hopes sent foreign investors piling into Samsung Electronics and SK Hynix. The catch: small caps fell and the won weakened.
Korea’s KOSPI closed at 6,579.04, up 3.68%, after Samsung Electronics rose 6.68%, SK hynix gained 5.54%, and futures rose fast enough to trigger a buy-side sidecar. Foreign and institutional buying overwhelmed heavy retail selling, while the KOSDAQ barely recovered from an early drop.