Korea Market Wrap Sep. 4: KOSDAQ +2.95%, Chips and Robots Lead

KOSDAQ’s 2.95% jump to 813.50 was the clearest signal from Korea’s September 4 session, while KOSPI added 1.64% to 6,687.21. This was more than an index rebound led by two mega-cap chip stocks. Foreign investors and domestic institutions returned as net buyers in both markets, the won strengthened to a 14-month high, and the rally broadened into semiconductor equipment, robotics, biotech and trading-sensitive stocks.

A change in sponsorship

Foreign investors bought a net KRW 503.4 billion of KOSPI shares and institutions added KRW 1.669 trillion, their first joint buying session in six trading days. Other corporations purchased another KRW 1.574 trillion, partly reflecting Samsung Electronics employee-compensation purchases and SK hynix buybacks for cancellation. Individuals sold KRW 3.723 trillion. On KOSDAQ, foreign and institutional net buying totaled KRW 262.3 billion and KRW 160.2 billion respectively, against KRW 411.9 billion of individual selling.

That shift matters because Korea’s previous rebounds had depended heavily on corporate flows and dip-buying. September 4 brought back conventional institutional sponsorship. Market breadth also improved: 549 KOSPI shares advanced versus 309 decliners, while KOSDAQ ended a four-session losing streak with a gain close to 3%. Participation was broad, but alpha remained concentrated. Samsung Electronics rose 2.20% and SK hynix 3.20%; on KOSDAQ, ROBOTIS surged 22.54%, Wonik IPS gained 9.33% and Jusung Engineering climbed 6.13%.

Three macro inputs aligned

The first catalyst was relief in global rates. After Federal Reserve Governor Christopher Waller signaled he could support keeping rates unchanged if inflation pressure continues to ease, the US 10-year Treasury yield slipped to 4.769%. That reduced the valuation penalty on long-duration technology and growth shares.

The second was currency support. Dollar-won closed at KRW 1,350.4 per dollar, down KRW 8.9 and its lowest regular-session close in roughly 14 months. A stronger won reduces near-term currency risk for offshore investors, even if exporters eventually face a translation headwind.

The third was evidence that Korea’s external surplus remains powered by semiconductors. The Bank of Korea reported a USD 42.08 billion current-account surplus for July, while semiconductor exports increased 176.3% from a year earlier. Investors treated those figures as confirmation that AI demand is reaching beyond memory prices into earnings, cash generation and the next equipment cycle.

Where the money moved

AI memory and semiconductor equipment ranked first. SK hynix and Samsung Electronics supplied index weight, while Wonik IPS and other equipment makers delivered higher beta. The price pattern suggests investors are beginning to price both strong current exports and future capital spending rather than a one-quarter inventory bounce.

Humanoid robotics was the second leadership cluster. ROBOTIS rallied 22.54% as investors focused on actuator demand, rapid sales growth in China, potential North American substitution away from Chinese suppliers and fresh brokerage coverage. Rainbow Robotics added 5.15%, showing that the move spread from components to a leading platform company.

Risk appetite also returned to health-care growth. Peptron gained 7.30% and ABL Bio 5.62%. New listing Sky Labs, which makes ring-based continuous blood-pressure monitors, finished its first KOSDAQ session 135% above its IPO price at KRW 23,500. Finally, lower volatility and bitcoin’s move above USD 80,000 boosted brokerage and digital-asset proxies: Mirae Asset Securities rose 3.77%, Galaxia Moneytree 10.87% and Woori Technology Investment 8.93%.

KSI view: repricing risk, not eliminating it

The session repaired confidence after the September 2 selloff and September 3’s extreme intraday reversal, but it did not remove the underlying macro risk. The market priced a lower probability of another Fed hike, a more stable won and durable chip exports. It did not produce a uniform large-cap rally: LG Energy Solution, Samsung Biologics and KB Financial all fell.

The next confirmation comes from the US August employment report. If a strong reading pushes the 10-year yield back above 4.8%, the most rate-sensitive winners could give back part of today’s move. If yields remain contained and foreign cash buying continues, KOSDAQ’s recovery above 800 would look more like normalization than a one-day short-covering rally. Investors should watch the persistence of foreign flows and whether breadth extends beyond chips and robotics before treating September 4 as a durable trend change.