US semiconductor stocks plunge 9% as investors unwind AI trades
Key points
- The Philadelphia Semiconductor Index (NASDAQ:SOX) fell approximately 9%, after briefly dropping more than 11%, as US chip stocks extended losses.
- Qualcomm (NASDAQ:QCOM) fell 11.2%, Arm Holdings (NASDAQ:ARM) dropped 11%, and Nvidia (NASDAQ:NVDA) declined 6.7%.
- Investors reacted to weaker technology earnings, uncertainty surrounding potential data centre regulations following US midterm election results and the unwinding of crowded, leveraged positions.
US semiconductor stocks fell sharply on November 5, 2026, as the Philadelphia Semiconductor Index (NASDAQ:SOX) declined approximately 9%, following a selloff that briefly exceeded 11%.
The decline extended losses from the previous session, as investors assessed weaker technology earnings and concerns that Democratic election victories could increase scrutiny of data centre construction and artificial intelligence infrastructure spending.
Qualcomm (NASDAQ:QCOM) fell approximately 11.2% after its smartphone chip sales missed estimates, while Arm Holdings (NASDAQ:ARM) declined 11% despite beating quarterly earnings estimates; Advanced Micro Devices (NASDAQ:AMD) dropped 13%, Micron Technology (NASDAQ:MU) lost 12.2%, and Western Digital (NASDAQ:WDC) and Sandisk (NASDAQ:SNDK) each fell approximately 16%.
Nvidia (NASDAQ:NVDA) declined as much as 6.7% in the reported market snapshot, while Broadcom (NASDAQ:AVGO) and Marvell Technology (NASDAQ:MRVL) fell 6.8% and 11.6%, respectively.
Following the selloff, the semiconductor index was down approximately 9.75% at 10,268.7 points in Reuters' intraday market report.
The semiconductor industry supplies processors, memory chips, networking components and other hardware used in smartphones, computers, vehicles, cloud computing and artificial intelligence systems.
The recent rally had lifted the semiconductor index by approximately 31% year to date, including the reported session's losses, while investors reassessed company valuations, AI infrastructure spending and the potential effects of tighter data centre development rules.
Frequently asked questions
More from United States
Lamar raises 2026 AFFO outlook to $8.97
Lemonade posts $336 million Q3 revenue, narrows loss
BD reveals $5.27 billion Q4 revenue, raises 2027 outlook
Cummins earnings surge to $1.14 billion as sales climb 13%
Six Flags reveals $1.17 billion Q3 revenue amid $366 million loss
EPAM Systems reports $1.43B Q3 revenue, expands buyback to $1.8B
