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Weekly wrap · Week of Oct 19 – Oct 23, 2026 · 5 trading days

KOSPI falls 2.1% and KOSDAQ 5.4% on AI spending doubts; Samsung E&A surges 37.2%

KOSPI−2.1%KOSDAQ−5.4%KOSPI 200−1.8%

Korean stocks ended a volatile week lower. KOSPI fell 2.1% to 5,550.3, KOSDAQ fell 5.4% to 751.69 and KOSPI 200 fell 1.8%. The main pressure came from renewed doubts about AI infrastructure spending: reports that Meta posted negative free cash flow and Tesla cut its capex outlook sent US chip stocks down 6.7% and the Nasdaq down 2.6% on October 22. KOSPI fell 3.5% that day. Semiconductor equipment fell 5.8%, chip testing and packaging 11.0%, EV batteries 3.8% and AI power and transformers 4.7%.

A second story was oil. Iran said seven tankers were attacked in the Strait of Hormuz, and Brent rose 8.0% on the week to $116.7. Oil, refining and chemicals fell 6.2%, with S-Oil down 13.9%. Shipping and logistics fell 6.4% and airlines 2.6%. On Friday KOSPI fell more than 4% intraday, then closed up 0.3% after SK hynix dropped its Solidigm US IPO plan.

Why the market moved

AI spending doubts after Meta's negative free cash flow report sent US chip stocks down 6.7%, while Brent above $110 added pressure; Friday's rebound followed SK hynix dropping the Solidigm US IPO plan.1234567

Top themes

Robots & humanoids

Physical AI platform launch lifts robot names12

Data-center supercapacitors

Large supercapacitor supply contracts123

  • Vina Tech, Data-center supercapacitor contracts+50.31%
  • Koses, Bloom Energy order, target raised+32.99%

China biotech deals

China pharma tie-up expectations123

The big stories

AI spending doubts after Meta cash-flow report sink chip stocks

Reports that Meta posted negative free cash flow and that Tesla cut its capex outlook revived doubts about AI infrastructure spending, sending US chip stocks down 6.7% and the Nasdaq down 2.6% on October 22. KOSPI closed down 2.08% for the period, with Samsung Electro-Mechanics down 5.56% and Samsung SDI down 7.45%.123456

Directly affected

Next in line

Further out

SK hynix drops Solidigm US IPO plan and rebounds

SK hynix halted its review of a US listing for Solidigm, its NAND subsidiary, citing the sharp fall in its share price and shareholder value concerns. The move eased worries about dual-listing discounts, and SK hynix closed up 0.39% for the period after a sharp intraday drop.12345

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Further out

Samsung E&A surges on earnings beat and ₩780B buyback

Samsung E&A reported third-quarter operating profit up 183.6% year on year, nearly double consensus, and announced a buyback of about ₩780 billion with ₩690 billion to be cancelled. The stock rose 37.15% over the period, with foreign and pension funds net buying.123456

Directly affected

Further out

Defense stocks fall; LIG Defense&Aerospace hit by bidding ban

Defense shares led the October 20 decline amid uncertainty over US military matters, and LIG Defense&Aerospace fell after a bidding ban. Over the period LIG Defense&Aerospace closed down 17.16% and Hanwha Aerospace down 10.81%.12

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Oil above $110 on Hormuz tanker attacks weighs on markets

Iran said seven oil tankers were attacked in the Strait of Hormuz, fuelling fears of a return to war, and Brent crude rose back above $110. The rise in oil prices added to pressure on Korean stocks at the open on October 23.1234

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Further out

Small caps surge on data-center supercapacitor and China deals

Vina Tech jumped 50.31% for the period after Binatech signed large supercapacitor supply contracts for data centers, while G2GBIO rose 59.54% on a China technology-transfer tie-up. Bigwave Robotics gained 49.48% on its physical AI platform launch.123456

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The market

KOSPI closed at 5,550.3 (-2.1%), KOSDAQ at 751.69 (-5.4%) and KOSPI 200 at 862.77 (-1.8%). Decliners (1,967) far outnumbered advancers (577). Trading value was about ₩23.2 trillion, below the ₩28.1 trillion average. Daily KOSPI moves were +1.8%, -3.7%, +3.3%, -3.5% and +0.3%. Overseas, the S&P 500 fell 0.5%, the Nasdaq 100 ETF 0.8%, the US chip ETF 3.1% and the Nikkei 225 4.0%. Gold fell 4.7%. The won strengthened 1.8% to ₩1,324.6 per dollar. The KTB 3-year yield stood at 3.803.

KOSPIDaily closes · shaded: this wrap5,550.3
6,0006,5007,000
Jul 13Aug 14Sep 16Oct 23
KOSDAQDaily closes · shaded: this wrap751.69
700800900
Jul 13Aug 14Sep 16Oct 23

577 stocks rose, 1,967 fell · trading value ₩23T

USD/KRW1,324.6−1.8%
KTB 3y3.8-5bp
UST 10y5-9bp
S&P 5007,622.86−0.5%
Nasdaq 100 (QQQ ETF)−0.8%
US chips (SOXX ETF)−3.1%
Nikkei 22562,693.16−4.0%
Brent oil116.72+8.0%
Gold4,007.9−4.7%
Copper (CPER ETF)−1.1%

Themes investors follow

Robots and humanoids rose 1.3%, led by NRobotics (+49.5%) and Bigwave Robotics (+49.5%), the latter after launching a physical AI platform. Biosimilars rose 0.9% with Samsung Biologics up 12.9%. Construction rose on Samsung E&A (+37.2%) though the group fell 0.4%. Decliners: non-ferrous metals -12.0% (Korea Zinc -9.7%), chip testing and packaging -11.0%, shipbuilding -8.4% (Hanwha Ocean -14.9%, HD Hyundai Heavy Industries -13.2%), K-defense -3.9% (LIG Defense&Aerospace -17.2%, Hanwha Systems -16.1%), solar and wind -6.4%, hydrogen -5.5%, power grid -5.4%, K-beauty -5.1% and biotech -2.3%. Small caps G2GBIO (+59.5%) and Vina Tech (+50.3%) led gainers.

Popular themes

Best themes

  • Sports & leisure+1.8%Samchuly Bicycle +18.0% · Mona Yongpyong +5.2% · E-World +4.9%
  • Robots & humanoids+1.3%NRobotics +49.5% · Bigwave Robotics +49.5% · Everybot +17.1%
  • Biosimilars+0.9%Samsung Biologics +12.9% · Celltrion +0.2% · Samsung Epis Holdings +0.2%
  • K-drama & film+0.7%Dexter studios +16.5% · Studio Mir +4.6% · ContentreeJoongAng +4.2%
  • AI software & services−0.3%Agent AI +61.9% · Flitto +41.0% · Polaris AI +28.7%
  • Games−0.3%Giantstep +48.9% · Kakao Games +12.5% · PearlAbyss +3.7%

Worst themes

  • Zinc & non-ferrous metals−12.0%Daiyang Metal −33.5% · Kukil Metal −15.9% · Korea Zinc −9.7%
  • Chip testing & packaging−11.0%Atum −18.9% · MKElectron −18.0% · SEMI Total Solution −17.4%
  • Shipbuilding−8.4%Hanwha Ocean −14.9% · Hanwha Engine −13.7% · HD Hyundai Heavy Industries −13.2%
  • Self-driving−8.4%Nextchip −10.5% · HL Mando −8.8% · StradVision −7.4%
  • Tires−6.7%Kumho Tire −13.9% · Hankook & Company −12.2% · Nexen Tire −5.5%
  • Solar & wind−6.4%CS Wind −13.5% · Hanwha Solutions −9.5% · Hanwha Solutions Pref. −6.1%

The biggest companies

Samsung Electronics was flat (0.0%) and SK hynix rose 0.4%, rebounding after the Solidigm decision. SK Square fell 1.1%. LG Energy Solution fell 4.9%, Samsung Electro-Mechanics 5.6%, Samsung SDI 7.4%, Hyundai Motor 5.3%, KB Financial 4.4%, Shinhan Financial 5.7% and KIA 3.0%. Hanwha Aerospace fell 10.8%. Samsung Biologics rose 12.9% and Samsung Life 2.7%; Celltrion and Samsung C&T were near flat. Sources cite record earnings and eased strike concerns for Samsung Biologics.

Who was buying and selling

Foreign investors were net sellers of about ₩719.2 billion on KOSPI and ₩674.3 billion on KOSDAQ. They bought Samsung Electronics (about ₩806.3 billion) and Samsung E&A (₩298.0 billion), and sold SK hynix (₩877.2 billion), Samsung Electro-Mechanics (₩255.1 billion) and Samsung Electronics Pref. Institutions bought Hanwha Ocean (₩463.0 billion), Samsung Biologics (₩203.4 billion) and Samsung E&A, and sold Samsung Electronics (₩487.1 billion). Retail bought Samsung Electro-Mechanics (₩344.7 billion) and sold SK hynix (₩831.1 billion) and Samsung E&A (₩418.8 billion).

Foreign investors

Net bought

  1. 1Samsung Electronics+₩806B0.0%
  2. 2Samsung E&A+₩298B+37.2%
  3. 3S-Oil+₩61B−13.9%
  4. 4GS Holdings+₩44B−8.0%
  5. 5Doosan+₩42B−5.9%
  6. 6Hyundai Engineering & Construction+₩41B−1.4%
  7. 7LIG Defense&Aerospace+₩39B−17.2%
  8. 8APR+₩32B−12.6%
  9. 9LG Innotek+₩30B−6.8%
  10. 10Tesco+₩28B−13.1%
  11. 11Hyundai Motor+₩27B−5.3%
  12. 12HD Hyundai Heavy Industries+₩26B−13.2%
  13. 13LG Electronics+₩25B−7.4%
  14. 14Sanil Electric+₩25B−9.3%
  15. 15NAVER+₩24B−3.6%

Net sold

  1. 1SK hynix−₩877B+0.4%
  2. 2Samsung Electro-Mechanics−₩255B−5.6%
  3. 3Samsung Electronics Pref.−₩239B+0.4%
  4. 4Daeduck Electronics−₩135B−5.7%
  5. 5Samsung SDI−₩84B−7.4%
  6. 6Woori Financial Group−₩65B−4.0%
  7. 7KB Financial Group−₩59B−4.4%
  8. 8Simmtech−₩59B−10.3%
  9. 9Hanmi Semiconductor−₩48B−9.0%
  10. 10Hyundai Mobis−₩48B−6.8%
  11. 11Samyang Foods−₩48B−0.3%
  12. 12Seojin System−₩46B−16.4%
  13. 13Samsung Biologics−₩45B+12.9%
  14. 14Ecopro BM−₩45B−13.2%
  15. 15Jusung Engineering−₩40B−14.5%

Institutions

Net bought

  1. 1Hanwha Ocean+₩463B−14.9%
  2. 2Samsung Biologics+₩203B+12.9%
  3. 3Samsung E&A+₩110B+37.2%
  4. 4LG Energy Solution+₩104B−4.9%
  5. 5Samsung Electronics Pref.+₩96B+0.4%
  6. 6Celltrion+₩91B+0.2%
  7. 7Daeduck Electronics+₩84B−5.7%
  8. 8LG CNS+₩76B+11.7%
  9. 9Samyang Foods+₩64B−0.3%
  10. 10Woori Financial Group+₩60B−4.0%
  11. 11Yuhan+₩60B+5.3%
  12. 12Hyundai Mobis+₩58B−6.8%
  13. 13HYBE+₩55B−0.2%
  14. 14KB Financial Group+₩53B−4.4%
  15. 15SK+₩38B+2.0%

Net sold

  1. 1Samsung Electronics−₩487B0.0%
  2. 2SK hynix−₩94B+0.4%
  3. 3Samsung Electro-Mechanics−₩91B−5.6%
  4. 4S-Oil−₩78B−13.9%
  5. 5Doosan−₩72B−5.9%
  6. 6LG Electronics−₩53B−7.4%
  7. 7SK Square−₩47B−1.1%
  8. 8HD Hyundai Heavy Industries−₩47B−13.2%
  9. 9Hyundai Engineering & Construction−₩41B−1.4%
  10. 10NAVER−₩38B−3.6%
  11. 11APR−₩37B−12.6%
  12. 12Tesco−₩35B−13.1%
  13. 13Isupetasys−₩34B−12.5%
  14. 14Doosan Enerbility−₩34B−8.1%
  15. 15Hyundai Motor−₩33B−5.3%

Retail investors

Net bought

  1. 1Samsung Electro-Mechanics+₩345B−5.6%
  2. 2Samsung Electronics Pref.+₩129B+0.4%
  3. 3Samsung SDI+₩86B−7.4%
  4. 4Hanmi Semiconductor+₩76B−9.0%
  5. 5Jusung Engineering+₩64B−14.5%
  6. 6Ecopro BM+₩63B−13.2%
  7. 7Simmtech+₩55B−10.3%
  8. 8Ecopro+₩50B−10.6%
  9. 9Daeduck Electronics+₩48B−5.7%
  10. 10SK Square+₩48B−1.1%
  11. 11Seojin System+₩43B−16.4%
  12. 12Doosan Enerbility+₩43B−8.1%
  13. 13Elice Inc.+₩40B+4.1%
  14. 14Hanwha Aerospace+₩36B−10.8%
  15. 15POSCO Holdings+₩34B−7.1%

Net sold

  1. 1SK hynix−₩831B+0.4%
  2. 2Samsung E&A−₩419B+37.2%
  3. 3Samsung Electronics−₩320B0.0%
  4. 4Samsung Biologics−₩155B+12.9%
  5. 5HMM−₩99B−3.6%
  6. 6Celltrion−₩88B+0.2%
  7. 7LG CNS−₩76B+11.7%
  8. 8LG Energy Solution−₩70B−4.9%
  9. 9Yuhan−₩65B+5.3%
  10. 10HYBE−₩38B−0.2%
  11. 11Samsung SDS−₩35B+6.8%
  12. 12LIG Defense&Aerospace−₩33B−17.2%
  13. 13Alteogen−₩29B−4.1%
  14. 14KIA−₩25B−3.0%
  15. 15GS Holdings−₩24B−8.0%

ETFs

The best ETFs were China humanoid robot funds: KODEX China Humanoid Robot +12.4% and TIGER China Humanoid Robot +9.5%, followed by construction ETFs (+8.0%, +6.4%) and WTI crude futures (+5.0%). US dividend ETFs also gained about 3%. The worst were KODEX US AI Optical Communication Network (-13.0%), defense funds (about -12% to -13%), semiconductor process funds (about -11% to -13%) and shipbuilding funds (about -11%), matching the weakness in AI, defense and shipbuilding.

Best ETFs

Worst ETFs

Leveraged and inverse ETFs are left out; moves are the daily moves compounded.

How our signals did

Squeeze! logged 27 setups: 6 reached TP1, 7 were stopped and 14 remain open. Kukdo Chemical (short) reached TP1 at +6.6% and Yangjisa (long) reached TP2. Technical events: 16 of 40 worked; Samsung E&A's breakout gained 7.9%, while Yangjisa's 200-day reclaim fell 12.8%. Twelve pairs were stretched and none had reverted, including KB Financial / Shinhan Financial and Hanwha Ocean / Samsung Heavy Industries. Short squeeze scores were highest for Meritz Financial Group and Hanssem (55 each).

Squeeze! setups

27 setups confirmed: 6 reached a target, 7 stopped out, 14 still open.

Notable technical signals

40 notable signals: 16 moved the way they pointed so far.

Pair trades

12 pairs stretched: 0 came back together since.

Highest short squeeze scores

Signals describe past prices. Results run from the signal to the latest close; they are not recommendations.

Written by AI from JONBUR's data and checked against those figures. Index and stock moves are the daily moves compounded over the period. Reasons come only from the linked daily wraps, news, filings and broker reports; when none gives a reason, we say so. Not financial advice.

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