The Tide Came Back, Only a Few Big Ships Rose

DAILY MARKET NOTE / 23 OCT 2026

A Comeback to the Day's High,
but Only One in Five Stocks Rose

The KOSPI closed at 5,550.30 ( +0.30%), after touching -4.12% intraday before recovering to the session highOnly 19.1% of KOSPI stocks advanced, almost unchanged from Oct. 22 (19.0%); KOSDAQ: -1.62%SK hynix accounted for the index's entire gain: an estimated 0.86 percentage-point contribution, roughly 2.9 times the net riseThe selloff was triggered by Meta’s AI-spending concerns; the Philadelphia Semiconductor Index: -6.72%Foreign investor net flow: KRW -994bn ; institutional net flow: KRW +872bn — a sharp divergence centered on SK hynix

The index recovered from a drop of more than 4%, yet only about one in five constituent stocks rose with it.

MARKET PATH / 01

-4.12% at the low, then rallied to +0.30% at the close—also the session high

When did the market tumble, and how did it come back?

IN PLAIN ENGLISHThe index plunged more than 4% within the first ten minutes of tradingIt never revisited the morning lowIt turned positive about 20 minutes before the close and finished at its high for the day

KOSPI · 09:00~15:30Sharp opening selloff → morning pullback → recovery after 12:30 p.m. → close at the high

OPEN5,403.17-2.36%

HIGH5,550.30+0.30%

LOW5,305.98-4.12%

CLOSE5,550.30+0.30%

THE READ

Peak sellingAt the open and through the first ten minutes: nearly the full impact of the U.S. chip-stock slump

RecoveryThe index set three successive higher highs after 12:30 p.m. and closed at the session high

Closing demandVolume in the final closing auction exceeded that of the opening five minutes

The catchEven after a +4.6% rebound from the low, only 19.1% of stocks advanced—a recovery confined to a few heavyweights

OPEN · MORNING

-2.36% Opened down, hit the day's low around 9:05 a.m.

Rebounded toward 5,450 by around 10 a.m.Slipped back toward 5,400 around 10:15 a.m.

MIDDAY

Near 5,400 at 11 a.m.; rising again after 12:30 p.m.

Around 5,390 at 11 a.m., more than 80 points above the morning lowNear 5,490 around 1 p.m.

AFTERNOON

Turned positive about 20 minutes before the close and finished at its high

Near 5,530 around 2:40 p.m.The KOSDAQ stayed below its previous close throughout the session and finished at 751.69

WHY / 02

Meta's AI spending worries sparked an opening plunge. Bargain hunting and SK hynix news fueled the recovery

Different catalysts drove the opening selloff and the intraday reversal

IN PLAIN ENGLISHConcerns over Meta's AI investment commitments drove the opening declineBargain hunters stepped in as investors judged some bad news already priced in, helped by an SK hynix disclosure

Meta's new nonvoting shares and rising spending commitments dragged U.S. chip stocks lower

Announcement will be created, with one new share distributed per existing share in January 2027

PurposeThe distribution itself raises no cash; the new class could later facilitate financing, acquisitions or compensation

CommitmentsAbout USD 825bn in spending commitments over several years, not the same as outstanding debt

U.S. sessionMeta -7% ; Nasdaq -2.60% · -6.72%

Core concernThe gap between AI spending and the cash it generates, rather than slowing demand; selling spread across chip stocks

-6.72%Philadelphia Semiconductor Index; memory and equipment makers fell even further

VIEW SUPPORTING DETAILS

Meta Q3: USD 64.6bn in revenue (+26%); free cash flow USD -2.12bn

Full-year capex outlook: USD 135bn–145bn, with the low end raised from USD 130bn

Commitment breakdown: uncommenced leases about USD 355.7bn; noncancelable contracts about USD 454.5bn; conditional cloud purchases up to roughly USD 14.7bn

Class C: board approval on Oct. 19; targeted effective date Jan. 19, 2027. Meta said it had no share-based capital-raising plan to announce at the time

Chips and equipment: Micron -6.3% ; Lam Research about -12% · KLA -10% or more; Applied Materials -8.2%

Memory and storage: SanDisk -8.5% ; Seagate -7.9% ; Western Digital -6.4% ; TSMC U.S.-listed ADRs -4.5%

What drove the reversal: bargain hunting as bad news looked priced in, plus the SK hynix disclosure

Priced inKOSPI on Oct. 22: -3.52% — analysts argued some of the bad news was already priced in, attracting bargain hunters

SK hynixAnnounced before the open that it had halted consideration of a Solidigm listing; the stock accounted for most of the index's rise CATALYST 06

AsiaThe Nikkei 225 dropped more than 1,400 points intraday before closing at -0.34% ; China’s ChiNext gained +4.16% . Afternoon recoveries were not unique to Korea

Samsung Electronics before the KRX open: -4.20% → +0.47% at the close — a reversal no single filing can explain

-0.34%The Nikkei 225 fell over 2% intraday but recovered most of that decline

VIEW SUPPORTING DETAILS

Japan: Nikkei 225 at 62,693.16, its lowest close since July 30; TOPIX -0.79%

China: Shanghai Composite +0.89% ; Shenzhen Component +2.79% ; ChiNext fell nearly 3% early on before rebounding

Samsung Electronics: KRW 205,500 before the open, KRW 206,500 at 9:25 a.m., KRW 215,500 at the close

Some strategists argue that fears of an imminent peak in AI investment are unfounded

MONEY / 03

Foreign investors sold SK hynix;
institutions absorbed almost all of it

Who moved the index today?

IN PLAIN ENGLISHForeign investors sold nearly KRW 1tn of KOSPI shares, with SK hynix their biggest net saleInstitutions bought almost the same amount of that stock, which then drove the index higher

Institutions · KOSPI cash equities

KRW +872bn

ReversalFrom a net flow of KRW -462bn on Oct. 22 to net buying today

ScaleLargest since Oct. 15 (KRW +1.693tn)

FuturesForeign investors bought futures worth KRW +451bn in contrast with their spot sales; institutions also bought KRW +83bn

About KRW +69bn compared with KRW +21bn on Oct. 22

KOSPI net buyersInstitutions and retail investors

KOSPI net sellersForeign investors

Net purchases by investor · KRW 100mn
Investor	KOSPI	KOSDAQ	Total
Foreign	-9,940	-420	-10,360
Institutional	+8,720	-250	+8,470
Retail	+530	+630	+1,160

Foreign investors, both markets: KRW -1.036tnInstitutions were modest net sellers on the KOSDAQ

Net purchases by stock · regular session · KRW 100mn
Stock	Foreign	Institutional	Retail
SK hynix	-5,595	+5,958	-165
Samsung Electronics	-1,914	+1,311	-41
SK Square	-1,004	+718	+268
Samsung Electro-Mechanics	-1,367	+354	+971
Samsung E&A	+1,756	-43	-1,825

Institutions' top three net buys matched foreigners' No. 1, No. 2 and No. 4 net sellsForeign investors sold Samsung Electro-Mechanics; retail investors bought itSamsung E&A ranked first for foreign net buying for a second straight day

DETAILED FLOWS

Futures and program trading · Oct. 23 vs. Oct. 22 · KRW 100mn
Category	Oct. 23	Oct. 22
ForeignKOSPI 200 futures	+4,510	+3,140
InstitutionalKOSPI 200 futures	+830	-1,500
RetailKOSPI 200 futures	-4,840	-930
Program	-130	-62
Non-arbitrageProgram	-7,216	-2,923
TotalProgram	-7,346	-2,985

Five sessionsKOSPI: foreign investors KRW -841bn ; institutions ; institutions ; retail investors KRW -886bn ; foreign futures KRW -496bn

Short sellingKOSPI KRW 1.0848tn (Oct. 22: KRW 1.0046tn); SK hynix ranked first at KRW 197.3bn

Foreign buysNos. 2–4: Hanwha Ocean KRW +20.6bn · GS KRW +15.7bn ; LG Innotek KRW +14.7bn

Foreign sellsNos. 5–7: Samsung SDI KRW -35.8bn ; KB Financial Group KRW -30.9bn ; Samsung SDS KRW -23.2bn

Institutional buysNos. 4–6: Samsung Biologics KRW +56.5bn ; Samsung Electro-Mechanics KRW +35.4bn ; Samsung SDS KRW +32.2bn

RetailNet buys: Samsung Electro-Mechanics KRW +97.1bn; Samsung SDI KRW +55bn ; No. 2 net sell: Samsung Biologics KRW -50.1bn

SECTOR / 04

Where the Strength—and Weakness—Was

The distribution of gains and losses tells more than a ranking

IN PLAIN ENGLISHThe index rose, but only one in five stocks advancedJust a few heavyweights, including SK hynix and Samsung Biologics, lifted the benchmarkEvery constituent declined in the secondary-battery, defense, shipbuilding and power-equipment groups

STRONG

Samsung BiologicsStock+7.71%

SK hynixStock+4.42%

PharmaceuticalsKOSPI sector+3.48%

Medical & Precision InstrumentsKOSPI sector+2.45%

WEAK

K-AI Defense TOP5+KRX thematic index-4.23%

Secondary Battery TOP 10KRX thematic index-3.38%

AI Power InfrastructureKRX thematic index-3.38%

MetalsKOSPI sector-3.22%

ChemicalsKOSPI sector-3.04%

KOSPIAdvancers: 19.1%, virtually unchanged from Oct. 22 (19.0%)

KOSDAQAdvancers rose from 16.3% on Oct. 22 to 23.7%

Both marketsDecliners: 74.0%

Roughly two boats in ten afloat: only 19.1% of KOSPI stocks rose

Estimated KOSPI index contributions · market-cap method · contribution in percentage points
Stock	Return	Contrib.
SK hynix	+4.42%	+0.86 pp
Samsung Electronics	+0.47%	+0.13 pp
Samsung Biologics	+7.71%	+0.11 pp
SK Square	+3.20%	+0.07 pp
All other stocks		-0.87 pp

Excluding SK hynix, the combined contribution was roughly -0.56 percentage points

ChipsTop 15 +0.23%, but only two of its 15 constituents advanced; cumulative two-session return -5.07%

Secondary batteries all 10 constituents fell for a second consecutive day; EcoPro -5.83% ; Samsung SDI -4.20%

Defense / ShipsAll constituents of those two themes and the power-equipment theme fell; Hanwha Systems -10.28%

Samsung BiologicsNo new filing. Broker analysts pointed to the postponement of a second union strike and renewed focus on Q3 results

Sector breadthOnly 12 of 56 pharmaceutical stocks and 14 of 80 electrical/electronics stocks advanced

SECTOR DATA

Rising and falling stocks · including limit-up/limit-down shares
Market	Advancing	Declining	Unchanged	Advancers
KOSPI	175	719	23	19.1%
KOSDAQ	412	1,248	81	23.7%

Oct. 22 and 23 · closing returns · two-day change vs. Oct. 21 close
Index / stock	Oct. 22	Oct. 23	Two days
KOSPIIndex	-3.52%	+0.30%	-3.23%
Semiconductor Top 15KRX thematic index	-5.29%	+0.23%	-5.07%
Secondary Battery TOP 10KRX thematic index	-6.37%	-3.38%	-9.53%
SK hynixStock	-5.49%	+4.42%	-1.31%
Samsung ElectronicsStock	-4.03%	+0.47%	-3.58%

Biggest declinersAhnLab -10.09% ; LS Materials -7.11% ; PharmaResearch -6.08% · S-Oil -5.29% ; Simmtech -5.02%

Advancing stocksSamsung E&A +7.94% (first day of its share buyback); SK Square +3.20% ; Samsung SDS +3.14%

Sectors · 20 common to both markets · sorted by KOSPI return
Sector	KOSPI	KOSDAQ
Pharmaceuticals	+3.48%	-0.55%
Medical & Precision Instruments	+2.45%	-1.56%
Electrical & Electronics	+1.27%	-2.01%
General Services	+0.88%	-1.75%
Manufacturing	+0.64%	-1.48%
Construction	+0.08%	-0.20%
Entertainment & Culture	-0.63%	-1.97%
Financials	-0.84%	-4.01%
IT Services	-0.98%	-1.30%
Transport & Warehousing	-1.09%	-0.88%
Paper & Wood	-1.14%	-2.03%
Food, Beverage & Tobacco	-1.21%	-0.59%
Distribution	-1.24%	-2.16%
Nonmetals	-1.34%	-1.65%
Textiles & Apparel	-1.76%	-1.25%
Telecommunications	-1.95%	-0.51%
Transportation Equipment & Parts	-2.22%	-0.75%
Machinery & Equipment	-2.57%	-1.42%
Chemicals	-3.04%	-1.62%
Metals	-3.22%	-2.24%

Market-specificKOSPI real estate +0.41% ; insurance +0.09% ; securities -1.23% ; KOSDAQ publishing and media reproduction -5.25%

Thematic indices · Korea Exchange · sorted by Oct. 23 return
Theme	Oct. 22	Oct. 23
Bio TOP 10	-3.00%	+1.44%
Blue Chip 25	-3.82%	+0.99%
K-AI Semiconductor TOP2+	-3.83%	+0.83%
Semiconductor Top 15	-5.29%	+0.23%
K-AI KOSDAQ Biotech	-3.16%	+0.05%
AI Semiconductors	-4.76%	-0.17%
Biotech Licensing	-2.81%	-1.12%
Internet TOP 10	-2.02%	-1.33%
BBIG	-2.82%	-1.39%
High-Dividend 20	-1.07%	-1.95%
Gaming TOP 10	-0.62%	-2.21%
Shipbuilding TOP 10	-2.96%	-2.53%
Electric Vehicle Top 15	-5.20%	-3.01%
Secondary Battery TOP 10	-6.37%	-3.38%
AI Power Infrastructure	-2.94%	-3.38%
K-AI Secondary Batteries	-7.26%	-3.79%
K-AI Defense TOP5+	-1.66%	-4.23%

Ten largest KOSPI stocks by market cap · closing price in KRW
Stock	Close	Change
Samsung Electronics	215,500	+0.47%
SK hynix	1,277,000	+4.42%
Samsung Electronics (preferred)	167,900	+0.48%
SK Square	775,000	+3.20%
LG Energy Solution	383,000	-1.79%
Samsung Electro-Mechanics	1,122,000	-2.01%
Samsung Biologics	1,466,000	+7.71%
Hyundai Motor	295,500	-1.99%
KB Financial Group	153,000	-3.29%
Samsung Life Insurance	245,000	+1.45%

Limit-up2 on the KOSPI and 8 on the KOSDAQ; no limit-down stocks in either market

CHANGE / 05

Yesterday's Questions, Today's Answers

Checking the conditions set in the previous session

YESTERDAY → TODAY

Institutional flows and trading value passed both checkpoints; semiconductors and batteries passed only the firstThe semiconductor rebound belonged to SK hynix; secondary batteries fell furtherTrading value rose from Oct. 22 but remained below its 20-day average

Number of rising indices: Semiconductor Top 15 and Secondary Battery TOP 10Stage 1: at least one up; Stage 2: both up. Only Stage 1 met

0/2

→

1/2

Institutional KOSPI cash-equity flows (KRW) · reduced net sellingStage 2: turn to net buying. Both stages met

-462bn

→

+872bn

KOSPI closes higher; trading value exceeds Oct. 22 (KRW)Stage 1: positive close; Stage 2: higher turnover. Both stages met

13.7003tn

→

16.4742tn

01 · Semiconductor Top 15 -5.29% → +0.23% ; Secondary Battery TOP 10 -6.37% → -3.38%03 · Trading value was 0.98× its five-day average and 0.85× its 20-day average

CATALYST / 06

SK hynix Drops Plans to Pursue a U.S. Listing of Solidigm

A single company announcement that the market visibly priced in today

SK hynix · disclosure before the Oct. 23 open

+4.42%

From the listing proposal to its cancellation

Aug. 5Plan disclosedOct. 23Review halted

SK hynix stops reviewing a Solidigm pre-IPO investment and public listing, easing double-listing worries but leaving U.S. factory funding unresolved

WHAT · The decision

DecisionThe company halted its review of a Solidigm / IPO

Filing language“After considering overall capital-market conditions”

SolidigmThe company formed after SK hynix acquired Intel's NAND business

TERMS · Size and purpose of the abandoned plan

Solidigm listing proposal · filings and press reports
Halted	Pre-IPO financing / IPO review
Valuation est.	Up to USD 150bn
Capital raise est.	Up to USD 15bn (about KRW 20tn)
Intended use	U.S. production capacity; less reliance on the Dalian, China, facility
Still required	New U.S. manufacturing capacity

Company's viewThe company needed to reassess whether a listing would be “the most advantageous choice for SK hynix and its existing shareholders”

ContextThe move followed regulators’ discussion of the plan as a potential

SHAREHOLDERS · What it means

Concern easedRisks of separately listing a subsidiary already owned through the listed parent

Open questionA new U.S. factory is still needed, but the proposed IPO route for investment and shareholder-return funding is off the table

AlternativesDirect investment, outside investors, third-party share issuance, borrowing or U.S. government support

Next updateWatch for explanations of financing and shareholder returns in the Oct. 28 Q3 earnings release

MARKET · The reaction

Pre-openKRW 1,194,000 (-2.37%); down less than Samsung Electronics (-4.20%)

CloseKRW 1,277,000 (+4.42%); holding company SK Square +3.20%

FlowsNo. 1 for foreign net sales and institutional net buying; see MONEY 03

NEXT / 07

What to Watch in the Next Session

Three tests for tonight and Monday, Oct. 26

Does the rebound broaden beyond SK hynix?

TodayJust 19.1% of KOSPI stocks advanced

Stage 1Above 19.1% on Oct. 26

Stage 2At least 40.7%, matching the Oct. 21 rebound

Does foreign selling of cash equities ease?

TodayKOSPI cash equities: KRW -994bn

Stage 1Net selling of less than KRW 994bn on Oct. 26 (including net buying)

Stage 2Switch to net buying

Can SK hynix hold today's rebound?

TodayClose: KRW 1,277,000

Stage 1Oct. 26 close of at least KRW 1,277,000

Stage 2Stage 1 plus a switch to foreign net buying, versus today's KRW -559.5bn

UPCOMING DATES

10/27~28 ; U.S. Federal Reserve policy meetingOct. 28 · SK hynix Q3 results · release before 9 a.m. · earnings call at 9 a.m.Next week · Samsung Electronics Q3 results and earnings releases from major U.S. tech companiesNov. 16 · Samsung E&A scheduled to disclose final Q3 resultsNov. 19 · End of SK hynix share-repurchase periodNov. 26 · Bank of Korea Monetary Policy Board meeting

The KOSPI erased a 4% drop in the first ten minutes to finish at its session high. Yet only one in five stocks rose with it. The next test: will the rebound spread beyond SK hynix?

SOURCES & DATA NOTES

As of Oct. 23, 2026. Index, sector and stock prices use Korea Exchange regular-session data, 09:00~15:30 ; overseas news and statistics are limited to information published by 8 p.m. KST Indices: KOSPI open 5,403.17, low 5,305.98; KOSDAQ open 748.32, high 753.02, low 732.87. Final regular-session figures, independently collected Intraday chart: indicative path based on five-minute bars; only open, high, low and close are confirmed values. Timing of the turn into positive territory: Financial News⁠·⁠Inssait ; intraday quotes: Asia Economy⁠·⁠EToday⁠·⁠Edaily ; volume is shown as relative bar height Flows: independently collected Korea Exchange regular-session data (investor totals at 3:38 p.m.; individual stocks at 3:51 p.m.). Foreign category includes other foreign investors. The “other corporations” figure is calculated from the investor-flow zero-sum balance; after-hours trades excluded Published closing-flow figures differ by outlet (foreign net sales from KRW -965.5bn to KRW -1.0938tn): EBN⁠·⁠Korea Economic Daily⁠·⁠NewsPim⁠·⁠EToday⁠·⁠MSToday Futures and program trading: KOSPI 200 futures by investor group at 3:49 p.m. (specific products and contract coverage not stated); program trades at regular-session close. Program flows and investor-class flows use different classifications and must not be added together. “Largest since” compares in-house data collected since Sept. 14 Market breadth: official Korea Exchange counts. Advancers include ordinary gainers plus limit-up shares (KOSPI 175 of 917; KOSDAQ 412 of 1,741). Short-selling totals combine Korea Exchange regular-session and Nextrade Main Market trades Sector returns and index contributions: Korea Exchange sector and thematic indices. Contributions are estimated as the change in each stock's market value divided by estimated total KOSPI capitalization on Oct. 22 (about KRW 4.568 quadrillion); they may differ from official index-point contributions Meta: Class C shares, SEC company filing ; spending commitments, SEC quarterly report ; CFO comments, Decrypt U.S. markets: index closes as of Oct. 22 local time (independently collected); stock moves and capex guidance, report citing Bloomberg ; Meta closing price, market diary ; summary, NewsPim Asia: Japan, NewsPim ; China, NewsPim Broker commentary: Han Ji-young of Kiwoom Securities on the bad news being priced in (Edaily); Yoo Seung-min of Samsung Securities on fears that AI spending has peaked (Financial News); Heo Hye-min of Kiwoom Securities on Samsung Biologics (Financial News); Lee Seok-hoon of Korea Capital Market Institute on Solidigm financing alternatives (Korea Economic Daily) Solidigm: filing language, Herald Business ; company explanation, IPO rationale and alternatives, SK hynix Newsroom ; history of the plan, regulatory comments and funding rationale, Korea Economic Daily ; valuation and fundraising estimates reported by Reuters (viaSaturday Economy); Intel NAND acquisition, Asia Economy ; pre-open price, MoneyToday Schedule: Fed meeting, Korea Economic Daily ; SK hynix earnings call, Bamsise (company 6-K) ; PMI, MTS Insights ; share-repurchase end date and Samsung E&A final earnings drawn from filings and news reports