Daily Pulse: September 15, 2026
KOSPI -0.85% | KOSDAQ +0.70% | Five straight sessions of foreign cash selling: KRW 1.53T (~$1.1B) today, SK Hynix and Samsung Electronics absorbing 83%
The Number That Matters
Foreign cash sold KRW 1.53T (~$1.1B) and futures sold 6,218 contracts in the same direction. SK Hynix absorbed KRW 997B (~$733M) and Samsung Electronics KRW 272B (~$200M), together 83% of total foreign selling and 7.4% of KOSPI turnover. The KOSPI opened at 6,659, reached 6,715, then closed at 6,627: the session gave back the entire morning gain and extended losses into the close.
Where the Money Went
Foreign net selling of KRW 1.53T (~$1.1B) concentrated in SK Hynix at KRW 997B (~$733M) and Samsung Electronics at KRW 272B (~$200M). Foreign buying across the top three names, SK Square at KRW 37B (~$27M), Samsung SDI at KRW 35B (~$26M) and LG Electronics at KRW 34B (~$25M), summed to KRW 106B (~$78M), 8% of the KRW 1.27T (~$933M) sold across the two largest foreign sell names. Institutions sold KRW 831B (~$611M) net; financial investment, the largest sub-category among the four this report tracks, sold KRW 585B (~$430M), alongside program trading net selling of KRW 855B (~$629M). Pension funds bought KRW 18B (~$13M) net, a nominal reversal after four prior sessions of selling. Retail bought KRW 705B (~$519M), with Samsung Electronics at KRW 342B (~$252M) the largest position. No foreign and institutional conviction buy existed today.
Why the Market Moved
1. SOX fell 5.86%, giving foreign sellers a global catalyst; cash and futures sold in the same direction for the fifth consecutive foreign cash selling session.
2. Program trading net sold KRW 855B (~$629M), amplifying institutional outflow.
3. The US 10-year yield held at 4.97%, sustaining valuation pressure on semiconductor names.
The Uncomfortable Question
Pension funds posted a nominal KRW 18B (~$13M) net buy after four sessions of selling. Foreign and institutional sellers together distributed KRW 2.36T (~$1.7B); pension fund buying covered less than 1% of that. The 83% semiconductor concentration in foreign selling has held across the last three sessions regardless of whether SOX rose or fell. The question is whether that concentration structure breaks, or whether foreign selling in the two names continues into a sixth session.
Key Disclosures Today
Kumho Petrochemical filed both a treasury share trust termination and a share cancellation decision on DART; no KRW amount was disclosed in the filing summaries.
KoreaAlpha Take
SOX fell 5.86% today. On September 14, when SOX rose 1.81%, foreign sellers still distributed KRW 2.96T (~$2.2B) in SK Hynix and Samsung Electronics. The global catalyst explanation does not hold across both sessions. The 83% two-stock concentration in foreign selling is structurally identical to the prior two sessions, and pension fund buying of KRW 18B (~$13M) against KRW 2.36T (~$1.7B) in combined foreign and institutional selling is not a floor: it is noise. The question the data cannot settle is whether foreign cash selling in these two names persists regardless of what SOX does overnight. The trade is simple: watch whether foreign net cash selling in SK Hynix and Samsung Electronics maintains the 83% concentration structure in the next session.
Data sources: Korea Exchange, DART, Bloomberg
Research only. Not investment advice. KoreaAlpha does not provide personalised recommendations.
Flow figures are KRX investor-type trading value across all listed boards (KOSPI, KOSDAQ, KONEX), common stock only, excluding ETF, ETN and ELW; institutions = the KRX institutional total investor type. Foreign, institutional and retail do not sum to zero: the balance, KRW 1.65 trillion (~$1.2B) net bought on this session, sits with other corporations and other foreign investors, categories this report does not collect.
