SK Hynix, the South Korean memory chipmaker, has crossed a $1 trillion market capitalization, making it the second South Korean company to hit that milestone, following Samsung Electronics.
The stock has risen over 200% year-to-date in 2026, on top of a 274% increase in 2025. The market valuation briefly peaked at approximately 1,624 trillion won, or around $1.08 trillion.
The surge is fueled by high-bandwidth memory (HBM)-specialized chips used in AI servers to feed data to processors fast enough for training large language models. SK Hynix is the dominant supplier of these chips, particularly to Nvidia, whose GPUs power most AI infrastructure.
AI data center buildouts by hyperscalers like Microsoft, Google, Amazon, and Meta have created unprecedented structural demand. SK Hynix got to market early with advanced HBM and maintains a technological lead competitors struggle to close.
Samsung, despite being larger overall, has been playing catch-up in HBM specifically. Micron also joined the trillion-dollar club recently, underscoring that the entire memory sector is being repriced by investors who see AI infrastructure spending as a multi-year trend.
On the bull side, AI spending shows no signs of slowing, and each new AI model generation is more memory-hungry. On the bear side, a stock up over 200% in a year carries risk, and memory chips remain a commodity business.