The Philadelphia Semiconductor Index fell by 9.2%, marking its largest single-day decline since June.

On Thursday, semiconductor stocks saw a sharp decline, extending the recent downward trend. As the Democratic Party put on a strong performance in the U.S. midterm elections, investors began to question the outlook for artificial intelligence trading themes. The Philadelphia Stock Exchange Semiconductor Index dropped 9.2%, on track for its largest single-day loss since June. It is down approximately 12% for the week so far; if this decline persists, it will mark the worst weekly performance since April 2025. The index is also set for its fifth consecutive weekly drop, the longest losing streak since April 2025. This selling pressure has also spread from chip manufacturers to other segments of the artificial intelligence supply chain. Storage device manufacturers Western Digital and Seagate Technology both fell by more than 14%; so-called “new cloud” firms CoreWeave and Nebius Group also recorded significant declines. However, not all investors on Wall Street have lost confidence in chip manufacturers. For example, Deutsche Bank indicated that compared with the software sector, the semiconductor sector remains attractive—especially considering that the investment value of semiconductor stocks still stands out relative to the software industry.