South Korea’s KOSPI rose about 5.2% on June 25, driven by gains in Samsung Electronics and SK Hynix, which account for over 55% of the market capitalization [1, 2]. Shares of SK Hynix and Samsung Electronics jumped after Micron Technology reported better-than-expected quarterly profit and revenue and forecasted strong demand related to AI, with customers committing US$22 billion to memory chips [1, 3, 2]. "Tech stocks received a massively needed shot in the arm after the bell when Micron delivered its earnings report," said Tony Sycamore, market analyst at IG [2].
SK Hynix plans to leverage investor interest in AI stocks by raising up to 45.45 trillion won (about US$29.52 billion) through a Nasdaq secondary listing [1]. JPMorgan analysts noted that "memory shortages were triggered by the explosive need for AI factory infrastructure... and we believe the role of memory as a strategic asset in Artificial General Intelligence remains unchanged" [1]. Qualcomm also forecasted US$15 billion in sales from its data center business by 2029, highlighting the robust outlook for chip-related sectors [2].
Japan’s Nikkei index jumped more than 3.5% on June 25, closing at a record high of 72,366.34 points, lifted by the AI chip sector after Micron’s forecast was released [3, 4, 2]. Japanese chip equipment makers like Advantest and Tokyo Electron surged between 7.8% and 15% as investors bought into the AI chip optimism [3, 4]. Takamasa Ikeda, senior portfolio manager at GCI Asset Management, said, "The Nikkei’s sharp gain is simply due to Micron’s earnings. The US semiconductor index, which is highly correlated with the Nikkei, will probably rise later in the day" [3].
Energy, mining and shipping stocks declined amid easing oil prices in Japan despite the broad market rally [3, 4, 2]. On June 24, KOSPI had rebounded sharply by 4.1% after a near 10% plunge the day before, led by retail investors buying the dip. "Retail investors going into leveraged ETFs is what is driving this volatility, as many were waiting for chances to go into the market out of FOMO (fear of missing out)," said Seo Sang-young, strategist at Mirae Asset Securities [5]. However, foreign investors were net sellers of South Korean shares worth 626.3 billion won on June 24, as the South Korean won weakened about 6.2% against the US dollar year-to-date 2026 [5].
Daisuke Hashizume, senior strategist at Daiwa Securities, noted investors locked in profits in technology stocks ahead of Micron earnings, but "they scooped up the shares today, and SoftBank Group was one of them" [4]. Nick Twidale, chief market strategist at ATFX Global, cautioned, "It’s a positive from Micron, but I’m not sure how long the euphoria will last across the rest of the sector... I think valuation concerns will continue to weigh on sentiment moving forward" [2].
The strong rally in Asian shares followed Micron’s better-than-expected results released after market hours on June 24 and continued into June 25 morning trade [1, 3, 4].
