The AI computing arms race continues to intensify, with the high-bandwidth memory (HBM) market landscape undergoing subtle shifts. In its latest research report, UBS stated that by 2027, Samsung is expected to catch up with SK Hynix in HBM bit shipments, each capturing approximately 40% of the market share, while Micron is projected to hold around 20%. This would mark a historic reshaping of the HBM market structure, carrying significant implications for investors in related sectors.

On the demand side, UBS has revised its 2026 terminal bit demand for HBM upward from 31.5 billion Gb to 32.9 billion Gb (an 88% year-over-year increase), and substantially raised its 2027 forecast from 53.9 billion Gb to 58.0 billion Gb (a 76% year-over-year increase). The primary driver for this adjustment is an upward revision in assumptions regarding Google's TPU procurement volumes.

Simultaneously, UBS has adjusted Nvidia's Rubin Ultra HBM configuration from the previously assumed 1TB (HBM4E 16-Hi) down to 768GB (HBM4E 12-Hi). The report notes that this "remains an evolving situation with no final decision yet," suggesting that this move reflects Nvidia's proactive measures to mitigate supply bottlenecks and address yield challenges associated with 16-Hi stacking and thermal compression bonding processes.

In terms of pricing, server memory price increases have also exceeded expectations. UBS has significantly raised its forecast for second-quarter DDR contract price growth from the previously projected +37% to approximately +60% (quarter-over-quarter), anticipating the average server DDR price to reach $1.95 per Gb. Some DDR5 quotes have already approached $2.10, marking a substantial jump from $1.15 in the first quarter. The forecast for third-quarter growth remains at +10%, with server DDR prices expected to approach $2.80 per Gb by the fourth quarter of 2027. For NAND flash memory, the second-quarter bound contract price increase forecast has also been adjusted upward from +40% to +60%, driven similarly by server SSD demand.

Samsung's Strong Comeback: Poised to Rival SK Hynix by 2027

Samsung's HBM resurgence is the most noteworthy highlight of this report. UBS maintains its 2026 HBM shipment forecast for Samsung at 9.7 billion Gb (a 124% year-over-year increase) but has significantly raised its 2027 projection from 20.3 billion Gb to 23.0 billion Gb (a 137% year-over-year increase), supported by Samsung's recent advancements in capital expenditure planning. If these projections materialize, Samsung and SK Hynix will each command 40% of the HBM bit market share by 2027, effectively splitting the market evenly.

In contrast, the report has slightly lowered its HBM shipment forecasts for SK Hynix—reducing the 2026 estimate from 18.4 billion Gb to 17.7 billion Gb (a 40% year-over-year increase) and the 2027 estimate from 24.7 billion Gb to 23.1 billion Gb (a 30% year-over-year increase). This adjustment is not due to a decline in HBM competitiveness but rather stems from persistent and strong customer demands for SK Hynix to allocate more production capacity toward DDR5 and LPDDR5X. The report explicitly emphasizes that HBM4 is not the supply bottleneck for the Rubin product line, which is set for volume ramp-up in the second half of the year.

Shifting Demand Dynamics: Nvidia's Dominance Declines, Google's Influence Rises Rapidly

From a customer structure perspective, Nvidia is expected to account for about 60% of HBM demand in 2026, but this share is projected to drop to 48% by 2027. Meanwhile, Google's share is anticipated to surge from 19% in 2026 to 27% in 2027, aligning with UBS's concurrent upward revisions for Broadcom and MediaTek forecasts.

In terms of product generations, HBM3E 12-Hi is expected to dominate in 2026 (accounting for 47% of the market), while HBM4 will become the core technology by 2027 (capturing 44% of the market), with HBM4E making up 21%. On the pricing front, the average per-bit price assumption for HBM4/HBM3E in 2027 has been revised from flat to a 30% year-over-year increase, while the premium for HBM4E over HBM4 remains unchanged at +50%.

Overall, UBS's monthly report conveys a clear message: the AI infrastructure construction boom continues to accelerate, the tight supply-demand balance in memory persists, and pricing trends are shifting upward across the board. Samsung's rapid catch-up is reshaping the HBM competitive landscape, and the emergence of a duopoly may arrive sooner than the market anticipates.