SanDisk weak guidance sends AI chip stocks tumbling on concerns over memory capex cycle cooling.

Memory and AI chip stocks fell sharply on Thursday after Sandisk issued disappointing revenue guidance, despite the company reporting better-than-expected quarterly results. The weakness in Sandisk shares dragged semiconductor stocks lower across both the U.S. and Asia.

The sector-wide pullback reflected investor concerns that AI-driven memory demand may be moderating from the exceptionally high expectations that have driven valuations in recent months.

Sandisk shares dropped approximately 8% at the opening bell, while Western Digital declined nearly 15% even after exceeding both earnings and outlook estimates. The weakness extended to Asia, where SK Hynix fell about 10% and Samsung Electronics declined nearly 6%, weighing on South Korea's Kospi index. In U.S. markets, Micron Technology and Seagate Technology each fell about 4%, while Advanced Micro Devices, Intel, Marvell Technology, Arm, and Texas Instruments all traded lower.

Analysts attributed the selloff primarily to investor concerns over softer memory pricing expectations rather than any fundamental weakening in AI demand itself. Demand from hyperscale data centers remains resilient, they noted, but the sector's elevated valuations have left it vulnerable to any indications of moderating growth.