SK Hynix’s NAND flash business is struggling to close a productivity gap with Samsung Electronics, Micron and China’s YMTC because its shift to newer manufacturing generations has been slower. In the second quarter of 2026, 176-layer NAND still represented 50–60% of SK Hynix’s production, while Samsung Electronics’ 236-layer NAND exceeded 60% and had become its mainstream generation. Micron’s 232-layer and 276-layer products accounted for 53% and 33%, respectively, while YMTC’s 232-layer NAND reached 68%. Kioxia and SanDisk retained substantial older-generation output but rapidly increased the share of their 218-layer BiCS8 product. Higher layer counts improve wafer productivity and cost efficiency, leaving manufacturers with older processes at a profitability disadvantage. SK Hynix’s NAND revenue share, including Solidigm, fell from 21.4% in the fourth quarter of last year to 16.4% in the first quarter of this year, while YMTC’s rose from 11.5% to 16.2%. Industry observers link the gap to delayed process-transition investment and SK Hynix’s capital-expenditure focus on DRAM and high-bandwidth memory. NAND capital spending declined from $3.5 billion in 2023 to $3 billion in 2024 and $2.9 billion in 2025. The company is investing more than $4 billion in an advanced packaging facility in West Lafayette, Indiana, targeting next-generation HBM mass production in the second half of 2029, with President and CEO Kwak Noh-jung saying HBM4E mass production would begin in the third quarter of 2029. The recent NAND price rally has limited the effect on actual earnings, but restoring NAND competitiveness is expected to be important for future margins and market position.