SK Hynix reported quarterly revenue of 104.6 trillion won and operating profit of 83.3 trillion won, with an operating margin approaching 80%. Yet net income plunged 58%. Despite the sharp decline in net income, the company’s U.S.-listed shares surged 13.3% on Oct. 28, while its South Korean shares rose 10.89%. The rally extended across the semiconductor sector, lifting Samsung Electronics 9.01%, Micron Technology 5.86% and SanDisk 7.66%. The market’s reaction reflected confidence in SK Hynix’s underlying operating performance rather than its headline net income. Strong shipment guidance, rising memory prices and progress in high-bandwidth memory (HBM) reinforced the company’s position in the AI supply chain. But the results also raise broader questions. How sustainable are its extraordina