SK hynix absorbed 59% of foreign investors' month of net selling in Korean stocks
SK hynix accounted for 12 trillion won of the 20.3 trillion won that foreign investors sold net on the KOSPI between Sept. 1 and Oct. 2. With Samsung Electronics included, two memory makers carried about 85% of it, leaving little foreign selling for the rest of the market.
The Investor · Invest desk
What happened
- Foreign ownership of SK hynix fell to 49.76% on Oct. 2, its lowest since the 49.46% recorded on May 15, 2023.
- Foreign investors were net buyers on only seven of the 22 trading sessions between Sept. 1 and Oct. 2.
- Foreigners' share of total KOSPI market capitalization fell to 39.66% over the month.
- Selling slowed at the start of October, with a net purchase of 243 billion won on Oct. 1 and a net sale of 190 billion won on Oct. 2.
Why it matters
- Who's exposed exposure SK hynix shareholders face the most foreign supply risk on the board, because foreigners still own the stock more heavily than they own the KOSPI as a whole, even after a month of selling.
- Who has to decide decision Brokerages have made third-quarter memory earnings the condition for foreign money to return, so a weak season would leave the chip-heavy KOSPI without the route back that analysts are counting on.
- What it limits constraint If Yuanta's Lee is right that flows wait on long-term rates, strong chip results alone cannot bring foreigners back, and Korean equity flows stay tied to rate moves in major economies.
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Take the two chipmakers out and the remainder is small. In Korea Exchange data, SK hynix's 12.009 trillion won and Samsung Electronics' 5.186 trillion won add up to 17.195 trillion won, about 85% of the 20.305 trillion won total [7][8][1][19]. That leaves roughly 3.1 trillion won of net foreign selling across every other stock on the main board for the month [20]. Foreigners sold a net 3 trillion won on Sept. 28 alone [4], so one session came close to matching a month of net selling in everything else [20].
The split inside the pair is uneven too, with hynix taking 2.3 times Samsung's selling [21]. The sources do not give index weights. Some of the concentration may be proportional selling in a market that is heavily weighted toward semiconductors, as Seoul Economic Daily describes it [17]. The ownership ratios are a better check. Even at its lowest in more than three years, foreign ownership of SK hynix sits about 10 percentage points above foreigners' 39.66% share of the KOSPI's total market value [6][5][24]. Samsung, at 46.41%, sits about 6.75 points above it [9][25].
Profit-taking after the first-half rally is the explanation both Seoul Economic Daily and the Korea Herald lead with [11]. It fits selling that lands hardest on the more heavily owned of the two chipmakers. Both outlets also cite the prolonged US-Iran war and rising interest rates in major economies [12]. A rates-driven cut to Korea exposure would also fall hardest on the largest foreign holdings, so the concentration by itself cannot separate the two explanations. There is a measurement issue as well: the totals include an after-market session that opened only on Sept. 15 [2], so the month does not compare cleanly with earlier ones.
In my view the profit-taking explanation fits the record best. Foreigners are trimming a memory position they still hold heavily, and the hynix ownership ratio tracks that better than the KOSPI total does. The view is wrong if chip shares steady after earnings and foreign selling then moves into the rest of the board, because that pattern would be a rates-driven exit from Korea. Lee Jae-won, an analyst at Yuanta Securities Korea, ties the recovery to rates. He said the shrinking scale of selling even on days of strong index gains, such as Oct. 1, "is the first sign that supply and demand could normalize once long-term interest rates stabilize" [16].
The early-October flows [10] are small against the period's average of about 923 billion won of net foreign selling per session [22]. Oct. 2's 190 billion won is about a fifth of that average [23]. Micron, the first of the three major memory makers to report, posted better-than-expected results on Sept. 30 [13]. "Macro jitters should peak this month, and the improved profit visibility after the third-quarter earnings season will serve as an incentive for foreign net buying," said Han Ji-young, an analyst at Kiwoom Securities [15].
What to watch
- Samsung Electronics' preliminary third-quarter figures, due around Oct. 8, the first Korean earnings test of whether memory profits hold up after Micron's beat.
- SK hynix's foreign ownership against the 49.46% low of May 15, 2023; a drop below it would mean foreigners kept cutting through the earnings season.
Information, not investment advice. This story is general information about companies and markets, drawn from cited reporting. It is not a recommendation to buy, sell or hold any security; check the cited sources before acting.
Clarity's read
What the record supports and how the coverage leans. The claims behind it follow.
Reality
- Evidence80
- Adoption
- Not scored
- Hype gap+5
- Incentives
- Not scored
- Confidence78
Claim ledger
Ranked by verification strength, evidence, and original report placement.
- [1]
Foreign investors recorded net sales of 20.305 trillion won on the KOSPI main board from Sept. 1 through Oct. 2, according to the Korea Exchange and Yonhap Infomax.
- [2]
The net sales figure includes trading in the after-market session, which opened on Sept. 15.
- [3]
Of the 22 trading sessions in the period, foreigners were net buyers on only seven.
- [4]
On Sept. 28, foreign investors sold a net 3 trillion won worth of shares in a single day.
- [5]
Sustained selling pushed foreign investors' share of total KOSPI market capitalization down to 39.66%.
- [6]
Foreign ownership of SK hynix fell to 49.76% as of Oct. 2, the lowest in about three years and four months since the 49.46% recorded on May 15, 2023.
- [7]
Foreign investors sold a net 12.009 trillion won of SK hynix shares during the period.
- [8]
Foreign investors sold a net 5.186 trillion won of Samsung Electronics shares during the period.
- [9]
Samsung Electronics' foreign ownership ratio stood at 46.41% after falling to 46.40% on Sept. 30.
- [10]
Foreign investors bought a net 243 billion won on Oct. 1 and sold 190 billion won the following day, considerably smaller moves than in September.
- [11]
The selling was attributed to profit-taking following the sharp rally in Korean equities, particularly large-cap semiconductor stocks, in the first half of the year.
- [12]
External uncertainties including the prolonged war between the United States and Iran and rising interest rates in major economies were cited as weighing on foreign investor sentiment.
- [13]
Micron Technology, the first of the world's three major memory chipmakers to report, posted better-than-expected results on Sept. 30.
- [14]
Samsung Electronics is scheduled to release preliminary third-quarter earnings around Oct. 8.
- [15]
"Macro jitters should peak this month, and the improved profit visibility after the third-quarter earnings season will serve as an incentive for foreign net buying," said Han Ji-young, an analyst at Kiwoom Securities.
- [16]
Lee Jae-won, an analyst at Yuanta Securities Korea, said the shrinking scale of selling even on days of strong index gains, such as Oct. 1, "is the first sign that supply and demand could normalize once long-term interest rates stabilize."
- [17]
Brokerages see a chance the selling will gradually ease; analysts said that if third-quarter earnings confirm the resilience of the memory chip market, foreign money could flow back into a Korean market heavily weighted toward semiconductors.
- [18]
SK hynix accounted for about 59.1% of foreign net selling on the KOSPI over the period.
- [19]
SK hynix and Samsung Electronics together accounted for 17.195 trillion won, about 84.7% of foreign net selling.
- [20]
Net foreign selling across all other KOSPI stocks was about 3.11 trillion won, roughly the size of the 3 trillion won sold on Sept. 28 alone.
- [21]
Foreign net selling of SK hynix was about 2.3 times that of Samsung Electronics.
- [22]
Average foreign net selling over the period was about 923 billion won per session.
- [23]
The 190 billion won of net selling on Oct. 2 was about a fifth of the period's average daily net selling.
- [24]
Foreign ownership of SK hynix is about 10.1 percentage points above foreigners' share of total KOSPI market capitalization.
- [25]
Foreign ownership of Samsung Electronics is about 6.75 percentage points above foreigners' share of total KOSPI market capitalization.
Sources
2 independent publishers whose own reporting we read for this story.
- en.sedaily.comForeigners Dump 20 Trillion Won in Korean Stocks in a Month
2 articles · October 4, 2026
- koreaherald.comForeign investors sell W20.3tr in Korean stocks, led by SK hynix and Samsung Electronics
1 article · October 3, 2026
Topics and entities
Topics
- Memory semiconductors
- Korean Equity Market
- Foreign portfolio flows