Memory-chip giants SK Hynix and Micron Technology each surpassed a $1 trillion market capitalization for the first time within 24 hours of each other, fueled by insatiable demand for the high-bandwidth memory (HBM) that powers AI accelerators. SK Hynix shares jumped as much as 13% in Seoul on Wednesday to a record high, while Micron surged more than 19% the prior day. UBS tripled its Micron price target from $535 to $1,525 a share.
Both firms dominate HBM, the specialized chips stacked alongside Nvidia's AI GPUs. SK Hynix, a key Nvidia supplier, has already sold out its entire 2026 HBM production capacity. Its stock has climbed roughly 250% since the start of the year and more than 1,200% since April 2025; Micron is up about 214% year-to-date.
SK Hynix becomes only the second South Korean company and the third Asian firm to enter the trillion-dollar club, after Samsung Electronics earlier this month and Taiwan's TSMC. The KOSPI index rose as much as 2.9% to a record 8,457 points.