Source: Sisa Journal · 경제

What happened

Foreign money flowed back into Korea’s chip giants on Monday, Sept. 7, reversing a week of heavy selling and lifting the main board toward the 7,000 line. Sisa Journal reports that Samsung Electronics and SK hynix both surged intraday after foreigners who had dumped more than 1.6 trillion won of the two names last week returned as net buyers. Samsung traded up 5.68% at 270,000 won; SK hynix rose 8.26% to 1,783,000 won. At the same moment, the KOSPI was up 4.61% at 6,995.39.

The breakdown

Foreign investors net bought 2.5533 trillion won on the main board. Samsung drew 881.7 billion won of foreign net buying; SK hynix took 1.3714 trillion won. Combined inflows into just those two stocks exceeded 2.2 trillion won — most of the day’s total foreign demand.

The swing from the prior week is sharp. From Aug. 31 through Sept. 4, foreigners net sold 1.9939 trillion won on the main board, including 518.1 billion won of Samsung and 1.0908 trillion won of SK hynix — a combined 1.6089 trillion won, roughly 81% of all foreign net selling in the period.

Global semiconductor sentiment had already turned before Korea opened. On Sept. 4 (U.S. time), the Philadelphia Semiconductor Index rose 3.37% even as the Dow, S&P 500, and Nasdaq all closed lower. Sandisk jumped 11.90%, SK hynix’s U.S. depositary receipt 8.14%, and Micron 6.10%.

Sisa Journal links the rebound to recovering appetite for semiconductor names after a steep correction, plus renewed focus on AI infrastructure after OpenAI unveiled GPT-6 Astra — reviving expectations for higher-capacity memory demand.

Why it matters outside Korea

Samsung and SK hynix anchor the global memory supply chain feeding AI data centers. When foreigners flip from net selling 1.6 trillion won of the pair to net buying more than 2.2 trillion won within a week, overseas flows can reprice Korea’s index — and global DRAM and HBM sentiment — faster than local earnings news. The Philadelphia Semiconductor Index’s 3.37% gain on a day the major U.S. averages fell shows chip stocks can decouple from macro moves, a pattern Korea amplified on Sept. 7.

What travelers and expats should watch

• Index headlines vs. your exposure: A 4.61% KOSPI jump driven by two chip names does not mean every Korea-listed stock you hold moved the same way. Check whether your pension, ETF, or brokerage basket is chip-heavy before treating the session as a broad recovery.
• FX timing around foreign-flow days: Large foreign net buying often coincides with won moves that do not mirror the equity headline. Compare your bank’s dollar rate at transfer time rather than assuming a green KOSPI screen means a stronger won.
• Overnight U.S. chip moves still lead: SK hynix’s ADR rose 8.14% on Sept. 4 before Korea’s Sept. 7 rally — Philadelphia semiconductor and ADR sessions can front-run the local open.
• Volatility cuts both ways: Last week’s 1.6089 trillion won foreign sell-off on the same two stocks shows how fast overseas funds can reverse.

Context

Read this as a foreign-flow reversal into memory leaders after a chip-led global bounce, not as proof Korea’s market has cleared last week’s selling pressure. Sisa Journal’s numbers show foreigners can dominate index direction through Samsung and SK hynix alone — buying more than 2.2 trillion won of the pair after supplying roughly 81% of the prior week’s foreign net selling.

Source

Sisa Journal · 경제: 외국인 돌아오자 ‘삼전닉스’ 껑충…SK하이닉스 8% 급등 — Korean original; paraphrased for briefing. Soft briefing only — not personalized investment, tax, or securities advice.