South Korean chip stocks plunge over 10% as U.S. inflation data sparks circuit‑breaker halts
On 15 Oct 2026 Samsung Electronics and SK Hynix fell 9.5% and 11.1% respectively after U.S. CPI showed 3.7% year‑on‑year growth, raising expectations of further Fed rate hikes. The sharp sell‑off triggered both the futures‑market sidecar and a Level 1 circuit breaker on the KOSPI and KOSDAQ, halting trading for 20 minutes. Foreign investors led the outflow, selling a net 3.62 trillion won of the two stocks, while leveraged ETFs tied to them lost about 77% of their listing value.
Why it matters
The circuit‑breaker activation shows heightened volatility and may limit intraday trading for investors in Korean equities. Foreign‑investor net selling of 3.62 trillion won adds pressure to the KOSPI, which fell 7.57%, potentially affecting portfolio valuations and risk‑management for funds with exposure to Samsung and SK Hynix.
Key facts
- 1Samsung Electronics closed down 9.5% after falling to a low of 204,500 won. ibtimes.com.au
- 2SK Hynix dropped 11.1% on the day. ibtimes.com.au
- 3The KOSPI closed down 454.59 points, or 7.57%, at 5,554.22. ibtimes.com.au
- 4Foreign investors sold a net 3.62 trillion won of Samsung and SK Hynix shares. ibtimes.com.au
- 5Circuit breakers were triggered at 9:07 a.m. (sidecar) and at 12:38 p.m. (Level 1) on the KOSPI. ibtimes.com.au
- 6Leveraged ETFs linked to the two stocks lost about 77% of their listing price, with a KRW 10 million investment now worth roughly KRW 2 million. asiae.co.kr
Summary written by AlphAI AI Desk from 20 of 23 sources. Not investment advice. Figures are as stated by the linked sources.