Korean Tech Giants Lead Historic Rebound Amid Semiconductor Sentiment Shift

The Korean markets experienced an extraordinary morning session, with the benchmark KOSPI surging 16.74% to 6,529.81 and the tech-heavy KOSDAQ climbing 9.33% to 704.96. The USD/KRW exchange rate hovered at 1,448.99 as massive buying interest returned to major technology and semiconductor heavyweights.

SK hynix (000660) +28.90%

P/E	P/B	EPS	Mkt Cap	ROE	Debt Ratio	52W Range
28.9	9.92	58,955	₩1,244.8T	61.16%	35.56%	245,000–2,987,000

SK hynix (000660) surged 28.90% following a volatile period where it plummeted 22.85% over two days [1] due to AI bubble concerns and negative foreign media assessments [4]. While Korea Investment & Securities issued a bold 4.7 million KRW target price [3][6], and Chairman Chey Tae-won made his first stock purchase of 4.8 billion KRW [2], the direct catalyst for today's massive rebound remains unconfirmed from the headlines. Additionally, SK hynix ADRs ranked first in overseas net purchases [5], though its direct impact on the stock's immediate movement is also unconfirmed.

SamsungElectronics (005930) +25.36%

P/E	P/B	EPS	Mkt Cap	ROE	Debt Ratio	52W Range
39.53	4.05	6,564	₩1,517.1T	19.16%	30.15%	67,500–374,500

Samsung Electronics (005930) jumped 25.36%, recovering from a steep sell-off [7][8] and pre-market plunge to the 1.6 million KRW range [11]. Recent downward pressure was heavily driven by foreign media warnings that the semiconductor decline was 'just the tip of the iceberg' amid AI bubble fears [10], which also dragged down Samsung C&T [12]. Although high dividends were discussed as a potential defense mechanism [9], the exact market catalyst driving today's dramatic 25.36% rebound is unconfirmed from the provided headlines.

SKSQUARE (402340) +29.91%

P/E	P/B	EPS	Mkt Cap	ROE	Debt Ratio	52W Range
15.62	4.95	66,468	₩137.0T	55.09%	7.50%	130,900–2,189,000

SK Square (402340) surged 29.91% to hit its daily limit [13][17]. The stock was propelled by positive cues from the US market and news of Chairman Chey Tae-won's stock purchase [16], which strongly revived investor sentiment across the semiconductor sector [13][14]. This dramatic rise marks a sharp reversal from July 28, when the stock tumbled over 9% to fall below the 1,000,000 KRW mark [15][18], heavily dragged down by the steep decline of its affiliate SK hynix [15].

Sources

1. SK하이닉스 –22.85%, 삼성전자 –17.91%…주가, 이틀 만에 빠졌다 — 한겨레 · 2026-07-29
2. 최태원, SK하이닉스 주식 첫 매수…48억 규모 — 연합뉴스TV · 2026-07-30
3. "SK하이닉스 470만원 간다"…주가 빠지자 나온 파격 전망 — 한국경제 · 2026-07-29
4. 삼성전자와 SK하이닉스 주가 하락은 "빙산의 일각" 외신 평가, AI 버블 우려 더 커져 — 비즈니스포스트 · 2026-07-30
5. SK하이닉스 ADR 해외주식 순매수 1위…세금 더 내는데 왜? — chosun.com · 2026-07-28
6. 주가 폭락 속…한국투자증권 "SK하이닉스 470만원 간다" — 연합뉴스TV · 2026-07-30
7. 삼성전자 주가, 오늘 왜 폭락했나? — Investing.com 한국어 · 2026-07-28
8. SK하이닉스 –22.85%, 삼성전자 –17.91%…주가, 이틀 만에 빠졌다 — 한겨레 · 2026-07-29
9. 주가 급락한 삼성전자, 역대급 배당이 방어막 되나 — 경제타임스 · 2026-07-29
10. 삼성전자와 SK하이닉스 주가 하락은 "빙산의 일각" 외신 평가, AI 버블 우려 더 커져 — 비즈니스포스트 · 2026-07-30
11. 삼성전자·하이닉스 프리마켓서 급락…23만·160만원대로 — 문화일보 · 2026-07-27
12. “삼성물산, 삼성전자 주가 부진에 덩달아 휘청”…목표가↓ — v.daum.net · 2026-07-29
13. 반도체주 투자심리 들썩…삼성전기·SK스퀘어 '상한가' 직행 - 머니투데이 — 머니투데이 · 2026-07-31
14. [특징주] 반도체 대장주 불기둥에.. SK스퀘어 등 관련주도 '급등' — 글로벌이코노믹 · 2026-07-31
15. [특징주] SK스퀘어, 하이닉스 급락에 100만원선 아래로…9%대 급락 — etoday.co.kr · 2026-07-28
16. [특징주] 美 훈풍·최태원 매수 소식에…SK하이닉스 ·SK스퀘어 20%대 급등 - 조선비즈 — Chosunbiz · 2026-07-31
17. SK스퀘어 주가, 상한가... 이유는? — 금강일보 · 2026-07-31
18. SK스퀘어 주가, 7월 28일 장중 964,000원 12.04% 하락 — 톱스타뉴스 · 2026-07-28

This is market commentary, not investment advice.