South Korea’s stock market staged a sharp rebound on Thursday, with KOSPI rising more than 5% during morning trading and a buy-side sidecar triggered as the move accelerated. Samsung Electronics and SK hynix led the rally, with Korean reports showing both chipmakers posting large gains during the session.
The immediate catalyst was SK hynix’s shareholder-return plan. The company’s move to acquire and cancel roughly ₩40 trillion of its own shares was interpreted as a strong signal of confidence in future earnings and capital generation. The announcement also lifted expectations that Samsung Electronics could expand its own shareholder-return program, although the larger figures being discussed for Samsung remain expectations rather than a confirmed commitment.
Why two chipmakers can move the whole index
The market impact is unusually large because Samsung Electronics and SK hynix together account for an enormous share of KOSPI capitalization. When both stocks move sharply in the same direction, they can pull the broader index with them. That made Thursday’s rally more than a single-company reaction: it became a test of whether shareholder returns can restore confidence after a period of extreme volatility in Korean equities.
For investors, the distinction between confirmed policy and expectation matters. SK hynix has provided the concrete catalyst; speculation about what Samsung may do next is part of the market’s pricing rather than an announced program. Intraday gains can also change quickly in a market that has recently seen repeated sidecars and unusually large daily swings.
What matters next is execution. Investors will watch the timetable and mechanics of SK hynix’s return plan, any formal shareholder-return decision from Samsung, and whether foreign and institutional buying continues after the initial surge. If those flows persist, the move could become a broader re-rating of Korea’s largest semiconductor companies rather than a one-day rebound.