Only 3 companies in the world have the technology to develop high-bandwidth memory (HBM), and SK Hynix holds 60% of the market share. Kospi: Rebounded on optimism over new government measures favorable to investors. SK Hynix surged 6.15% after BlackRock disclosed a 5% stake. Nvidia CEO Jensen Huang publicly stated: 'Without HBM memory, there are no AI supercomputers.'