Korean Stocks Surge, Triggering Trading Halt on Micron's 'Surprise' Earnings

South Korea's benchmark KOSPI index surged over 5% on June 25, triggering a temporary trading halt, known as a 'sidecar,' for program-based buy orders. The Korea Exchange (KRX) announced the activation of the sidecar at 9:07:03 AM, a mechanism designed to curb volatility by pausing program buying for five minutes when the KOSPI 200 futures index rises by 5% or more for at least one minute. This marks the fifth such sidecar activation this month, according to Hankyoreh.

The sharp rise in the KOSPI is largely attributed to the 'surprise' earnings announcement by Micron Technology, a major global memory semiconductor manufacturer alongside Samsung Electronics and SK Hynix. Micron reported a significant increase in its third-quarter (March-May) revenue, reaching approximately 64 trillion Korean won (about $41.46 billion USD), a 345.7% jump year-over-year. Its operating profit margin also reportedly increased by over 10 percentage points from the previous quarter, reaching 81.2%.

Following the announcement, Micron's stock surged over 15% in after-hours trading, with other semiconductor-related stocks like SanDisk and Seagate also experiencing sharp gains. This performance has been described by one analyst as an 'all-time surprise,' suggesting it may quell debates about a peak in artificial intelligence (AI) demand, according to Hankyoreh.

Korean semiconductor giants Samsung Electronics and SK Hynix saw their shares climb significantly in early trading. Samsung Electronics rose over 4%, trading at 355,000 to 358,000 won, while SK Hynix surged over 9% to 10%, trading at 2.83 million to 2.84 million won. These gains follow previous increases for both companies the day before. Samsung Electronics also recently announced plans for a 90 trillion won share buyback, and SK Hynix is reportedly pursuing a Nasdaq listing for its American Depositary Receipts (ADRs) next month, further contributing to their stock performance, according to Yonhap.

Amidst the market activity, the won-dollar exchange rate opened at 1,543.0 won per dollar, a 1.2% increase from the previous day's closing price.