The KOSPI jumped 5.23% to 6,809.58, while the KOSDAQ rose 2.06% to 841.48, reflecting a broad market rally. The surge was anchored by major semiconductor players announcing historic shareholder‑return programmes and a supportive backdrop from the U.S. chip sector. The won stood at 1,411.93 per dollar.
SK hynix (000660) +11.47%
Analyst consensus — 22 ratings, last 180 days · avg target ₩3,347,727
SK Hynix surged 11.47% to close sharply higher. The move follows the company's announcement of a historic shareholder‑return program that includes a 40 trillion‑won share buyback and full cancellation of the acquired shares, signalling that management believes the stock is undervalued. The news sparked an over‑8% jump in after‑hours trading and was reinforced by a tailwind from the U.S. semiconductor market. The precise driver of the 11.47% intraday gain cannot be confirmed from the headlines alone.
SamsungElectronics (005930) +6.87%
Analyst consensus — 22 ratings, last 180 days · avg target ₩492,500
Samsung Electronics rose 6.87% amid optimism around a joint 300‑trillion‑won annual shareholder‑return plan announced with SK Hynix, which analysts expect will bolster earnings and investor confidence. A separate report hinted at a potential catalyst that could trigger another price explosion, though specifics were not disclosed. Recent coverage also highlighted a 77% three‑month rally for investors who bet on the stock, underscoring strong market sentiment.
SKSQUARE (402340) +7.67%
Analyst consensus — 5 ratings, last 180 days · avg target ₩1,956,000
SK Square posted a 7.67% gain despite earlier pressure from the SK Hynix fallout. Earlier headlines reported that a decline in SK Hynix led analysts to cut SK Square’s target price, causing a 10‑11% drop in its shares ([14],[16],[17]). On August 19, however, the stock benefited from a rebound in semiconductor sentiment, with reports of a 10% intraday rise even as U.S. chip stocks weakened ([15],[18]). The net effect was a notable intraday advance.
SK eternix (475150) +7.44%
Analyst consensus — 3 ratings, last 180 days · avg target ₩62,000
SK Eternix climbed 7.44% after a series of sentiment‑boosting events. Institutional investors expanded their holdings on August 18, a development that lifted market confidence and helped the share recover to the 60,000‑won level ([23]). Positive chatter labeling the stock a “big hit” for the next session further fueled short‑term buying ([22]). Nonetheless, after three consecutive days of rapid gains, the stock showed an intraday decline on August 19, suggesting a possible correction ([21]).
Alteogen Inc. (196170) +10.21%
Analyst consensus — 3 ratings, last 180 days · avg target ₩413,333
Alteogen surged 10.21% on the KOSDAQ. The rally was driven by expectations that the company’s ALT‑B4 therapy will be expanded globally, a theme highlighted in an August 20 feature ([25]). A breaking‑news report on August 19 noted a sharp price jump during the NXT platform session, adding further momentum ([27]). The specific reason for the closing‑price rise on August 19 was not detailed in the available headlines ([26]).
Sources
- SK하이닉스 주가, 오늘 하락하는 이유는? — Investing.com 한국어 · 2026-08-18
- SK하이닉스, 40조 자사주 사들여 전량 소각…시간외 주가 급반등 — 조선일보 · 2026-08-19
- 배당 대신 '국내 최대' 40조 주식 소각 꺼낸 SK하이닉스…"주가 저평가 판단" — 뉴시스 · 2026-08-19
- "SK하이닉스 주가 하락 반영" SK스퀘어 목표주가↓-NH - 머니투데이 — 머니투데이 · 2026-08-17
- “장 끝나니 오르네”…SK하이닉스, ‘역대급 주주환원’에 8% 넘게 급등 — 에너지경제신문 · 2026-08-19
- SK하이닉스 주가 장중 5%대 올라, 미국 반도체주 훈풍에 SK스퀘어도 강세 — 비즈니스포스트 · 2026-08-18
- 삼성전자, SK하이닉스 주가 전망 : 이번 상승세로 다시 전고점 회복할 수 있을까? — 네이버 프리미엄콘텐츠 · 2026-08-16
- [투자노트] 삼성전자 주가, 다시 한번 폭발할 수 있는 계기는 ‘이것’ - 조선비즈 — Chosunbiz · 2026-08-17
- 불닭으로 번 돈 삼성전자에 넣었더니…3개월 만에 77% 껑충 — 주간조선 · 2026-08-18
- '35만원vs65만원' 삼성전자 엇갈린 전망…800만 주주 어디로 — 대한데일리 · 2026-08-18
- 삼성전자 ETF 반토막, 설계대로 작동한 결과였다 — sisain.co.kr · 2026-08-18
- "삼성전자·SK하이닉스 연간 최대 300조원 주주환원"...코스피 반등 열쇠될까 — 조선일보 · 2026-08-16
- SK스퀘어, 반도체 반등 시 주가 탄력도 높을 것 By 알파경제 alphabiz — Investing.com 한국어 · 2026-08-18
- "SK하이닉스 주가 하락 반영" SK스퀘어 목표주가↓-NH - 머니투데이 — 머니투데이 · 2026-08-17
- SK스퀘어 주가 장중 10%대 내려, 미국 반도체주 약세에 삼성전자 7%대 하락 — 비즈니스포스트 · 2026-08-19
- NH證 SK스퀘어, SK하이닉스 주가 조정 반영…목표가↓ — 아주경제 · 2026-08-17
- [특징주] SK스퀘어, SK하이닉스 급락에 100만원선 아래로 — 뉴스핌 · 2026-08-19
- [오늘의 주목주] SK스퀘어 주가 11%대 내려, 코스피 반도체 투심 위축에 6470선 하락 마감 — 비즈니스포스트 · 2026-08-19
- SK이터닉스 주가, 8월 18일 장중 59,600원 2.23% 상승 — 톱스타뉴스 · 2026-08-18
- SK이터닉스 주가 3거래일 ‘폴짝’…연휴 뒤 6만원 고지 넘을까, 숨 고를까 — CBC뉴스 · 2026-08-16
- SK이터닉스 주가, 8월 19일 장중 58,300원대 하락세 — 톱스타뉴스 · 2026-08-19
- [적중! 대박 예감] 'SK이터닉스, 온코닉테라퓨티스' 내일장 예감 좋은 대박 종목은? — v.daum.net · 2026-08-18
- 18일, 기관 보유 비중 확대... 자이에스앤디, SK이터닉스, 티씨머티리얼즈 등 — 씽크풀 AI · 2026-08-18
- SK이터닉스 6만원 회복 — CBC뉴스 · 2026-08-18
- [특징주]알테오젠, 또 뛴다…ALT-B4 글로벌 확장에 주가 ‘들썩’ — 남도일보 · 2026-08-20
- 알테오젠 주가 5,500원 상승 후 장마감 — 아시아뉴스통신 · 2026-08-19
- [속보] 알테오젠 장전 NXT서 주가 급등 — CBC뉴스 · 2026-08-19
This is market commentary, not investment advice.