Micron and SanDisk fall again as investors trim AI memory bets

Micron and SanDisk shares fell in Wednesday premarket trading as investors trimmed two of 2026's largest memory positions, with Micron down about 2% and SanDisk roughly 3% following Tuesday's declines of 4.5% and 4.3%. The selloff reflects concerns over whether extraordinary memory shortages, pricing, and margins can persist as new capacity arrives, triggered by China's ChangXin Memory Technologies planning DDR5 server memory with a denser architecture. Tuesday marked Micron's fourth straight loss, pressuring the Philadelphia Semiconductor Index. Analysts note commercial viability of CXMT's technology remains unproven, while ASML's raised forecast showing AI-driven demand exceeding capacity through 2028 suggests the AI infrastructure cycle remains intact, shifting debate to who captures profits as supply increases.