SK Hynix crossed a $1 trillion market capitalization for the first time on Wednesday, closing 9.3% higher on the Korea Exchange as demand for high-bandwidth memory chips used in AI data centers continued to tighten supply across the industry.
At its intraday peak, the stock climbed 14.9% before pulling back, with the chipmaker's total market value hitting a record 1,680 trillion won — equivalent to roughly $1.12 trillion. Samsung Electronics had first cleared the $1 trillion threshold on May 6, and Micron $MU Technology followed just one day earlier, on Tuesday.
SK Hynix, Samsung, and Micron now form the three dominant suppliers of high-bandwidth memory, sitting at the center of the global AI infrastructure buildout. Counterpoint Research data cited by Bloomberg show that as of last year's fourth quarter, SK Hynix commanded 57% of global HBM revenue, leaving Samsung and Micron with 22% and 21% shares, respectively. April earnings results showed quarterly profit multiplying fivefold, and the company projected that demand for HBM chips would outpace available supply over the coming three years.
Year to date, the three chipmakers have all posted extraordinary gains, with Micron leading at roughly 245%, SK Hynix close behind at about 215%, and Samsung adding approximately 149%.
Buoyed by the chipmaker surge, the Kospi touched an intraday high that represented a 5.1% advance before settling at a 2.3% gain by the close; the two Korean memory giants together represented half of the benchmark's total market capitalization, according to Reuters. The Kospi has risen 95% so far this year.
Wednesday also marked the debut of single-stock leveraged ETFs tied to Samsung and SK Hynix on the Korea Exchange. A leveraged SK Hynix product targeting double the stock's daily return surged 18% on its first day of trading, according to Bloomberg.
The AI memory rally follows a broader revaluation of the sector. Micron's market capitalization crossed $690 billion earlier this month after a research report from IDC argued that AI had driven an "unprecedented inflection point" for memory, breaking from the industry's historical boom-and-bust cycle.
The company is separately pursuing a U.S. listing through American depositary receipts; analysts at Barclays wrote in a recent note that such a debut could provide additional upward momentum for the shares, according to Bloomberg.