Samsung Electronics is aggressively closing in on market leader SK Hynix in the high-bandwidth memory (HBM) market, lifting its share by 12 percentage points in a single quarter. The gap between the two South Korean chipmakers has narrowed to 17 percentage points.

According to market research firm Counterpoint Research on September 3, SK Hynix maintained the top spot in the global HBM market with a 50% revenue share in the second quarter of 2026. However, that was down 8 percentage points from 58% in the prior quarter, and a sharp 14 percentage points below the 64% recorded a year earlier.

Samsung Electronics’ upward momentum was striking. Its share, which stood at just 15% in the second quarter of last year, climbed from 21% in the first quarter of this year to 33% in the second quarter—more than doubling in a year. As a result, the gap with SK Hynix shrank from 37 percentage points in the first quarter to 17 percentage points in the second, less than half the previous level.

Micron held third place at 18% in the second quarter. The U.S. chipmaker had maintained a 21% share from the second quarter of last year through the first quarter of this year, but slipped 3 percentage points this quarter. Its gap with Samsung widened to 15 percentage points.

The quarterly HBM revenue share trend for major players is as follows:

CompanyQ2 2025Q3 2025Q4 2025Q1 2026Q2 2026SK Hynix64%56%57%58%50%Samsung Electronics15%23%22%21%33%Micron21%21%21%21%18%

Note: Counterpoint Research data, revenue basis

Samsung’s latest surge coincides with the ramp-up of HBM4 shipments. Samsung became the industry’s first to begin mass production of HBM4 in February this year, and reached $1 billion (approximately 1.4 trillion won) in HBM revenue just four months after starting volume shipments. SK Hynix, by contrast, began HBM4 shipments later than Samsung and remains dependent on its existing flagship HBM3E product.

Behind Samsung’s competitive edge in HBM4 is a DRAM process that is a generation ahead. Samsung was the industry’s first to apply 10-nanometer-class sixth-generation (1c) DRAM to HBM4. This contrasts with competitors that used fifth-generation (1b) DRAM—the same technology used in HBM3E—for their initial HBM4 products. The 1c DRAM’s finer process allows more data to be stored in the same area and offers advantages in power efficiency and performance.

Samsung’s strengths are also reflected in the base die. The base die, which sits at the bottom of the HBM stack and connects multiple DRAM dies to the graphics processing unit (GPU), is produced using Samsung’s in-house 4-nanometer foundry process. This represents the full-scale leveraging of Samsung’s unique advantage as a company with both memory and foundry businesses in HBM4.

Performance improvements are also notable. Samsung’s HBM4 reliably achieves speeds of 11.7 gigabits per second (Gbps), 22% higher than HBM3E’s maximum speed of 9.6 Gbps. It can reach up to 13 Gbps.

Counterpoint Research expects Samsung’s share to gradually increase further as HBM4 shipments ramp up. The majority of current HBM revenue is still generated from HBM3E, with HBM4 shipments expected to become meaningfully visible starting in the second half of 2026.

Samsung’s internal outlook is also optimistic. Kim Jae-june, head of strategic marketing at Samsung Electronics’ memory business, said during the second-quarter earnings conference call that “HBM4 revenue in the third quarter will expand more than threefold compared to the previous quarter, and HBM4 will account for more than 60% of total HBM revenue in the second half.” He also noted that “considering the time required for physical capacity expansion and yield stabilization, the memory semiconductor supply shortage will continue through 2028,” forecasting that the supply shortfall will widen further next year.

Samsung had stated during its July conference call that it would “secure a share of the HBM market equivalent to its share of the overall DRAM market” in the second half of this year. Samsung’s global DRAM market share in the second quarter was 39%, putting its 33% HBM share close to that target.

SK Hynix remains confident in defending its lead. Kim Ki-tae, head of HBM sales and marketing at SK Hynix, said during the second-quarter conference call that “HBM4 competitiveness is only complete when a company can deliver the performance customers demand and supply it in volume with stable yields and quality,” emphasizing the company’s solid partnership with Nvidia. SK Hynix’s position is that the competitiveness it has accumulated across product performance, mass-production yield, quality, and customer trust is a differentiator that is difficult to replicate in a short period.

Meanwhile, the pursuit by China’s CXMT is another variable to watch. CXMT recorded a double-digit share of 10% in the global DRAM market for the first time in the second quarter. This came as major players like Samsung and SK Hynix focused on advanced memory competition in HBM, tightening supply in the commodity DRAM market—a gap CXMT has aggressively exploited. Some foreign media outlets have also reported that CXMT is producing HBM3E in small volumes.

HBM4 is slated to be featured in Nvidia’s next-generation AI accelerator, the “Vera Rubin” series. With HBM4 unit prices significantly higher than HBM3E and demand surging amid Big Tech’s race to develop new chips, competition among the three memory makers for HBM4 supply leadership is expected to intensify further in the second half.