South Korea’s KOSPI crashed more than 8% on June 23, triggering circuit breakers twice, as Japan’s Nikkei 225 broke an eight-session winning streak in a broad selloff driven by US technology stocks.
The moves extended a turbulent stretch for Asian equities as Tuesday’s tech-driven reversal erased early gains across the region. Benchmarks in Taiwan, South Korea, and Japan had each climbed at least 40% this year, making the concentrated semiconductor trade the most exposed when US megacap sentiment shifted.
The KOSPI opened at 9,083.54, down 0.34% from the prior close, then collapsed through the 9,000, 8,900, and 8,800 levels and all the way down to 8,500 in rapid succession. The Korea Exchange triggered a sell-side circuit breaker at 11:40 a.m., then activated a first-stage circuit breaker around 2:40 p.m. as the index sank to 8,375.31, an 8.11% decline on the day.
Wall Street set the tone. Alphabet fell 4.99% after two high-profile AI researchers left the company for rivals. SpaceX shed 16%, its third straight losing session, after the company announced a large investment-grade bond offering that rattled confidence in AI capital spending.
In Tokyo, the Nikkei 225 snapped its recent record run, and is also in freefall, down almost 3% at the time of publishing.
Foreign investors are at the source of the collapse, as there has been net selling in KOSPI shares. Samsung Electronics fell 8.77% to 322,500 won. The drop extended a historic session from the prior day, when Samsung lost the top KOSPI market-cap position to SK Hynix for the first time in 26 years. SK Hynix itself fell a massive 11.55 % to 2.582 million won, despite Micron surging 6.82% overnight.
Han Ji-young of Kiwoom Securities noted that the Magnificent Seven weakness and rising Treasury yields weighed on growth stocks, while falling oil prices tied to US-Iran ceasefire talks could partially cushion the rate burden.