The US technology-heavy Nasdaq Composite ended October with its steepest monthly decline since March 2025, reflecting growing investor concerns about the financial returns from large-scale artificial intelligence investments.
The index fell approximately 5.3% during October, according to market data reported after the final trading session on October 30. The decline followed a difficult final week for technology stocks, with the Nasdaq dropping approximately 2.9% on Friday to close at 25,437 points.
Editorial Insight
Key Highlights
Important points readers should notice.
The Nasdaq Composite declined approximately 5.3% in October 2026.
It recorded its worst monthly performance since March 2025.
The index fell approximately 2.9% on October 30.
The Nasdaq closed at 25,437 points on the final trading day of October.
Concerns about the scale and returns of AI investments weighed on technology shares.
Amazon and Intel financial updates added to investor uncertainty.
Investor concerns intensified after earnings reports and spending outlooks from major technology companies renewed questions about the cost of expanding artificial intelligence infrastructure. Technology companies have been committing substantial capital to data centres, advanced computing systems and semiconductor hardware to support the development and deployment of AI services.
However, investors are increasingly examining whether the expected revenue and profits from these investments will justify the scale of spending.
Amazon and Intel came under particular pressure following their latest financial updates. Amazon's significant AI-related investment plans and cash outflow raised questions about future spending, while Intel's financial outlook and warning about cash burn disappointed investors.
Editorial Analysis
Why This Matters
The Nasdaq's decline highlights the growing scrutiny of artificial intelligence investment across the technology industry. Major companies are spending heavily on data centres, advanced chips and computing infrastructure. Investors want clearer evidence that these investments can produce sustainable revenue and profits. The market movement is also important for investors with exposure to US technology shares and funds tracking major stock indexes. It demonstrates how changes in expectations about corporate spending and profitability can influence the wider financial market.
The pressure also extended to semiconductor companies and other businesses associated with the AI infrastructure sector. The sell-off reflected a broader reassessment of technology valuations and expectations surrounding the commercial returns from artificial intelligence.
The Nasdaq's monthly decline contrasted with the performance of the Dow Jones Industrial Average, which recorded a monthly gain. The difference highlighted the pressure concentrated in technology and growth-oriented shares during October.


