This is a follow-up to Why Korea Part 5: Korea’s Stock Market Is Now Near Global No. 6. That post asked why Korea’s market cap has exploded. This one asks a more practical question: who was buying, and who was selling?
TL;DR
- Foreign investors did not simply abandon Korea. They sharply reduced Samsung Electronics and SK hynix, the two AI-memory mega-caps.
- Research OS local DB shows foreign net selling of KRW 89.2T across 2,730 Korean stocks from Jan. 2 to May 22, 2026. Samsung Electronics contributed KRW -50.4T and SK hynix KRW -34.4T. Together: KRW -84.8T, or roughly 95% of total net selling.
- Samsung Electronics rose 127.6% YTD while foreigners sold KRW 50.4T and foreign ownership fell from 52.37% to 48.39%.
- SK hynix rose 186.7% YTD while foreigners sold KRW 34.4T. This looks less like thesis abandonment and more like distribution after an extreme HBM-led rally.
- The portfolio conclusion is: hold core memory exposure, avoid chasing, and watch whether foreign buying rotates into non-memory sectors with real earnings.
1. The Main Decomposition
| Segment | Foreign net buying |
|---|---|
| Korea total, 2,730 stocks | KRW -89.2T |
| Samsung Electronics | KRW -50.4T |
| SK hynix | KRW -34.4T |
| Ex-Samsung Electronics | KRW -38.8T |
| Ex-Samsung Electronics + SK hynix | KRW -4.4T |
The key line is the last one. Excluding Samsung Electronics and SK hynix, the foreign outflow shrinks to KRW -4.4T. The better description is therefore:
Foreign investors were not primarily selling Korea. They were cutting Korea’s AI-memory mega-cap exposure.
Seoul Economic Daily similarly reported that from May 7 to May 22, SK hynix and Samsung Electronics accounted for more than 83% of foreign net selling on the KOSPI. (Seoul Economic Daily)
2. Samsung Electronics: Strong Price, Foreign Distribution
| Item | Value |
|---|---|
| Period | 2026-01-02 to 2026-05-22 |
| Price | KRW 128,500 → KRW 292,500 |
| YTD return | +127.6% |
| Intraday high | KRW 300,500, May 22 |
| Foreign net buying | KRW -50.4T |
| Institutional net buying | KRW +6.3T |
| Retail net buying | KRW +29.2T |
| Foreign ownership | 52.37% → 48.39% |
Samsung Electronics remains a core Korean equity. But this was not a foreign-led rally. Foreigners sold through most of the move, while domestic liquidity absorbed the supply.
The most important interval was May 7-May 22. Samsung rose another 7.7%, while foreigners sold KRW 18.9T. That is a sign of a strong market, but also a sign of heavy distribution near the top. Yonhap also reported that on May 7 Samsung reached the “270,000 won” level despite large foreign selling in both Samsung Electronics and SK hynix. (Yonhap)
3. SK hynix: Even Stronger HBM Leadership, Same Distribution Pattern
| Item | Value |
|---|---|
| Period | 2026-01-02 to 2026-05-22 |
| Price | KRW 677,000 → KRW 1,941,000 |
| YTD return | +186.7% |
| Intraday high | KRW 1,995,000, May 15 |
| Foreign net buying | KRW -34.4T |
| Institutional net buying | KRW +9.2T |
| Retail net buying | KRW +24.1T |
| Foreign ownership | 53.81% → 51.66% |
SK hynix is the purer HBM beta, which explains why it outperformed Samsung. Foreign selling here does not mean the company is weak. It means a very successful position is being reduced.
The fundamentals remain powerful. SK hynix reported KRW 52.5763T in 1Q26 revenue, KRW 37.6103T in operating profit, and a 72% operating margin, citing strong AI infrastructure demand and high-value memory products. (SK hynix / PR Newswire)
4. What Foreigners Bought Instead
Foreign buying was much more diversified than foreign selling.
| Rank | Stock | Foreign net buying |
|---|---|---|
| 1 | Doosan Enerbility | KRW +2.15T |
| 2 | Celltrion | KRW +1.42T |
| 3 | Samsung SDI | KRW +1.25T |
| 4 | APR | KRW +1.15T |
| 5 | Hanwha Ocean | KRW +0.76T |
| 6 | Doosan Robotics | KRW +0.65T |
| 7 | SK Inc. | KRW +0.63T |
| 8 | Hyundai Engineering & Construction | KRW +0.60T |
| 9 | Doosan | KRW +0.56T |
| 10 | POSCO Holdings | KRW +0.52T |
The rotation map is clear: energy infrastructure, biotech, batteries, K-beauty, shipbuilding/defense and robotics received selective inflows. Opinion News described a similar rotation from semiconductor profit-taking toward Doosan Enerbility, Celltrion, Samsung SDI, APR and Hanwha Ocean. (Opinion News)
5. Investment Read-Through
| Asset or basket | View | Rationale |
|---|---|---|
| Samsung Electronics | Hold core, pause additions | Strong price action, but foreign structural rebuying is not yet visible |
| SK hynix | Watch, no chase | HBM leadership is real, but foreign selling is extreme |
| Celltrion | Buy on pullback candidate | Foreign buying plus lower correlation to AI hardware |
| Samsung SDI | Conditional buy | Strong foreign accumulation, but battery-cycle recovery still needs proof |
| Hanwha Ocean | Watchlist | Good shipbuilding/defense setup, but recent foreign flow cooled |
| Doosan Enerbility | Hold/watch | Strong YTD foreign buying, weaker recent flow |
| Doosan Robotics / Padu / Seojin System | Avoid chasing | Strong momentum, but price risk is high |
Bottom Line
The right sentence is not “foreigners sold Korea.”
It is:
Foreigners sold Korea’s AI-memory mega-caps while selectively rotating into energy infrastructure, biotech, batteries, K-beauty, shipbuilding/defense and robotics.
That does not kill the Korea thesis. But it changes the trading discipline. Samsung Electronics and SK hynix are still core holdings, not fresh-cash priority buys until foreign buying returns or the stocks digest the distribution.
Data source: Research OS local DB, prices_daily, investor_flow_daily, foreign_ownership_daily, through 2026-05-22. Flow values are estimated from local daily investor-flow data and may differ from final exchange totals.
Disclaimer: For research and information purposes only. Not investment advice.