SK Hynix Jumps 12% as Big Tech Doubles Down on AI Memory
May 4, 2026 - 8:41 am
A $725bn hyperscaler capex ramp and a 20% HBM price rise have made the South Korean chipmaker the second-most valuable company on the KOSPI. The harder question is when supply catches demand.
There is a small joke in semiconductor circles about which part of an AI server is most expensive. The graphics processor used to be the obvious answer. For the past 18 months, increasingly, it has been the memory soldered next to it.
On Monday, the market priced that joke.
SK Hynix, the South Korean memory specialist that supplies the bulk of the world’s high-bandwidth memory for AI accelerators, climbed as much as 12% in Seoul, with shares hitting roughly 1.4 million won, or about $970, in morning trading, according to Reuters. The rally made SK Hynix the second-most valuable company on the KOSPI, behind only Samsung Electronics, and reflected foreign buying that followed strong earnings and reaffirmed AI infrastructure plans from US hyperscalers the previous week.
It is, by any measure, a remarkable run for a company most consumers have never heard of.
The trigger is straightforward. Big Tech’s combined 2026 capital expenditure is on track to land somewhere between $650bn and $725bn, depending on which analyst’s tally one trusts, an increase of roughly 77% on 2025. Microsoft has guided to as much as $190bn for the calendar year, with its chief financial officer publicly attributing about $25bn of that to rising memory-chip and component costs. Meta, in its Q1 update, raised its own range to $125–145bn, citing similar pressures. Amazon’s Andy Jassy has committed roughly $200bn. Google has not been quieter. Practically all of this money flows, in one form or another, towards AI training and inference clusters; a meaningful share of it lands in the bill of materials for high-bandwidth memory, where SK Hynix dominates.
By late 2025, SK Hynix held an estimated 57% of the global HBM market, according to figures cited by analysts at Counterpoint and others. That share is unusually concentrated for a commodity-adjacent business, and it is the structural reason the company’s earnings now look more like those of a software platform than a memory house.
SK Hynix’s first-quarter operating profit, reported on 23 April, was a record. Operating margins on its memory line, by some sell-side estimates, are running above 70%.
Margins of that order do not last forever. They do, however, last as long as supply lags demand.
Why supply is not catching up
HBM is not ordinary DRAM. It is a stacked, 3D-packaged memory built to feed bandwidth-hungry GPUs, and producing it requires a specific set of advanced packaging steps that the industry, including Samsung and Micron, has been slower to scale than buyers would like. According to TrendForce, both Samsung and SK Hynix have raised HBM3E prices by roughly 20% for 2026, and supply is being booked years in advance by hyperscalers and accelerators.