US stock exchanges rose — investor optimism toward the AI sector is restored

On Wednesday, significant gains were recorded on US stock exchanges. Demand for technology company shares was boosted by several positive developments in the artificial intelligence sector: an improved forecast from cloud services provider CoreWeave, strong interest in Anthropic's initial public offering (IPO), and sharp growth in OpenAI's revenues.

In recent days, the American stock market has been characterized by high volatility. The unstable period began last week with the Democratic Party's convincing victory in the midterm elections. The initial rally was followed by a massive sell-off, as a result of which the S&P 500 posted its worst weekly performance since the week of the so-called "Liberation Day" in April 2025.

Pressure on the market was intensified by a sharp decline in artificial intelligence sector stocks and stricter expectations regarding the Fed's interest rate decisions.

However, buying on the dip and optimism driven by CoreWeave's results gave the market an opportunity to recover. This week, the S&P 500 and the tech-focused Nasdaq Composite have already fully offset last week's significant losses.

The technology sector drove the index gains

At the close of Wednesday's trading session, the Nasdaq Composite rose 1.6% to reach 25,466.19 points. The S&P 500 ended trading up 1.3% at 7,616.75 points. The Dow Jones Industrial Average showed comparatively modest growth, rising 0.5% to reach 52,484.76 points.

According to Christian Olesen, founder and portfolio manager of Olesen Value Fund, any signal of relative easing in monetary policy from Fed officials, or an unexpected positive development in the AI sector, could push the market toward new records in the short term.

However, in his view, US investors remain overly optimistic, and stock valuations — particularly in the technology sector — are high. Olesen believes that a significant portion of some companies' market prices is based on speculative expectations, which means the risks in the market are more skewed to the downside.