SK hynix Ships 12-Layer HBM4E Samples to Customers

SK hynix confirmed via its official newsroom release that it has shipped samples of its 12-layer HBM4E to major customers, entering the same customer-qualification stage that Samsung Electronics reached roughly three weeks earlier, on May 29, when Samsung claimed the industry's first 12-layer HBM4E shipment. SK hynix did not contest that claim; instead it pointed to its track record supplying HBM3, HBM3E, and HBM4 at scale, positioning manufacturing experience as its differentiator rather than speed. The 12-stack part delivers a maximum of 16Gbps per pin and 48GB of capacity via Advanced MR-MUF packaging, a process that injects protective material between stacked dies, with power efficiency improved more than 20 percent over HBM4 and thermal resistance cut by 17 percent. Ahn Hyun, SK hynix's President and Chief Development Officer, said the company has 'laid the foundation to strengthen its AI leadership with HBM4E' and would work to reinforce its position 'as a full-stack AI memory creator.'

SK hynix currently holds roughly 58 percent of the HBM market versus Samsung's approximately 21 percent, with Micron also pushing into next-generation production, per Counterpoint Research cited by The Korea Herald. That means this shipment is less about catching up and more about defending share heading into the next memory generation. HBM4E is expected to anchor Nvidia's Rubin Ultra accelerator platform next year, which is why both leading suppliers are pushing through qualification now: a confirmed design win in Rubin Ultra, or in competing platforms, will largely determine revenue for the next cycle of HBM demand.

Sample delivery marks entry to customer validation, where accelerator vendors test the memory inside their actual platforms, not a production commitment. Neither SK hynix nor Samsung has disclosed a mass-production date or named which customers received samples. Teams planning infrastructure around next-generation memory supply should treat this as a qualification-stage milestone rather than a supply guarantee: validation still has to clear thermal management, PCB routing, power delivery, and memory-controller/PHY compatibility in target accelerators before production adoption follows.

Track supplier qualification milestones with Nvidia and other accelerator vendors, system-level benchmarks once HBM4E ships in production hardware, and whether SK hynix's market-share lead holds as Samsung and Micron advance their own next-generation roadmaps.