MicroStrategy HBM4 Win: SK and Samsung Capture Vera Rubin Memory Share, Micron Excluded

According to a SemiAnalysis report, the memory supply for NVIDIA's (NVDA-US) next-generation AI chip platform, Vera Rubin, is shifting. Micron (MU-US) is expected to miss full-year production due to its proprietary HBM4 Base Die failing thermal performance and not reaching the 11Gbps pin rate required. SK Hynix and Samsung Electronics, with stable 10Gbps and 11.7Gbps transfer rates respectively, are set to capture the entirety of the Rubin HBM4 market. Full production of Vera Rubin is accelerating, with supply chain certification expected to be largely complete by January 1, 2026. Samsung is forecast to receive 20%–30% of initial orders, while SK Hynix is expected to secure the majority of the core share. SK Hynix benefits from deep integration with TSMC's advanced packaging to overcome thermal challenges, while Samsung leverages vertical integration via its own logic and DRAM processes. Micron's continued focus on proprietary design has left it lagging in TSV stacking and signal integrity. This outcome underscores the shift in HBM4 competition toward ecosystem integration, with South Korean vendors establishing dominance.