SK Hynix reported a 76% operating margin for Q2 2026, up from 41% a year earlier, as the artificial-intelligence memory boom reshaped semiconductor profitability. Operating profit reached 60.54 trillion won, roughly $41.7 billion, marking a 557% year-over-year increase, while gross margin climbed to 83%. The company holds approximately 58% of the global high-bandwidth memory (HBM) market, compared with Micron's 21%. HBM is specialized memory used directly with AI accelerator chips, making it essential to large AI data-center build-outs. In Q1 2026, revenue reached 52.58 trillion won, operating margin was 72% and operating profit totaled 37.61 trillion won. SK Hynix still slightly missed some analyst forecasts, highlighting how elevated expectations have accompanied its rapid growth. Micron crossed a $1 trillion market capitalization in May 2026, after SK Hynix reached a similar valuation earlier this year. SanDisk, focused on NAND flash rather than DRAM, recently reported a 78.4% gross margin and projected margins above 80% through 2030. SK Hynix gained its HBM lead by moving earlier and more aggressively to qualify chips with Nvidia and other AI chip designers. Micron's significant U.S.-based manufacturing provides a geopolitical advantage that SK Hynix and Samsung cannot replicate. HBM also differs from commodity memory because it requires complex manufacturing, advanced packaging such as chip stacking and lengthy qualification for specific AI chip designs, creating switching costs and supply constraints.