EL7.AI
StocksMedium•26 October 2026•
4 min read

S&P 500 rises 0.7% as Anthropic filing tests investor appetite for AI

Key Facts

1The S&P 500 rose 0.7% on October 26, 2026, while the Dow Jones gained 0.3% and the Nasdaq Composite rose 0.8%.
2Anthropic's revenue exceeded $16 billion in the first half of 2026, equivalent to 14 times its level a year earlier.
3Anthropic posted a net loss of $80.7 billion in the first half of 2026, compared with $13 billion in the same period.
4The Philadelphia Semiconductor Index rose about 3% in the session but remained down nearly 12% in October.
5Markets priced in a 12.7% probability of a rate hike at the Fed meeting before the October 28, 2026, meeting.

U.S. stocks closed higher on Monday, October 26, with the S&P 500 up 0.7%, the Dow Jones adding 0.3% and the Nasdaq Composite rising 0.8%, according to the Associated Press. The gains came on the day Anthropic filed for an IPO, bringing it closer to a potential listing next month. Reuters said the filing gave stock futures a brief lift and helped support sentiment toward AI stocks. But the advance did not end volatility in the sector, as borrowing costs and the expense of financing data centers and buying chips remained concerns for investors. The session also came as the S&P 500 and Nasdaq were recovering from two consecutive weekly declines, Reuters reported.

Nvidia led part of the gains, rising 2.5% and providing the biggest boost to the market in the session, according to the Associated Press. By contrast, gains in semiconductor stocks were not enough to erase their weakness this month: the Philadelphia Semiconductor Index rose about 3% on Monday but remained down nearly 12% in October, Reuters reported. Other AI-linked stocks remained volatile as investors worried about the cost of borrowing to build data centers and buy chips. An investment official at RWA Wealth Partners said the session leaned optimistic on the Anthropic announcement, adding: "Everything today is about the Anthropic announcement, so I would say we are back to a somewhat optimistic bias." He warned that volatility could continue as further announcements come out during the week.

Anthropic's filing puts the company to the test in the IPO market, after market volatility trimmed the fall listing calendar and rising borrowing costs heightened investor concerns about the debt-funded AI investment boom, Reuters reported. The agency said the cost of the resources needed to build AI systems is pushing Anthropic, OpenAI and SpaceX's AI unit to spend more than they generate in revenue, fueling bubble fears. An investor cited by Reuters said the IPO's outcome would indicate whether investors were willing to continue supporting capital spending on AI development. Anthropic says in its prospectus that its main objectives include raising capital and increasing financial flexibility, and creating a public market for its shares. It was not yet clear how much the company would raise, its final valuation or the offering price, according to the Associated Press.

The offering document shows rapid revenue growth alongside a sharp widening in losses. Anthropic's revenue exceeded $16 billion in the first half of 2026, equivalent to 14 times revenue in the same period a year earlier, according to the Associated Press. The company, however, posted a net loss of $80.7 billion in the first half of 2026, compared with a loss of $13 billion in the first half of 2025. The agency said the losses were much lower after excluding certain items. The registration document said the company plans to list its shares on the Nasdaq Global Select Market under the symbol ANT. The figures add to investor questions about whether AI companies can turn expansion and heavy spending into returns as they compete to build the infrastructure they need.

Investors are focused this week on results from major technology companies, with more than a third of S&P 500 companies scheduled to report, including Alphabet, Microsoft and Amazon, according to Reuters. The focus will be on whether their heavy AI spending translates into growth. The Federal Reserve's monetary policy statement was also scheduled for Wednesday, alongside growth and inflation data on Thursday. Reuters reported that markets priced in a 12.7% probability of a rate hike at Wednesday's meeting, according to the CME FedWatch tool; that does not mean the committee's decision is settled. Economists surveyed by the Associated Press expected gross domestic product to grow 1.7% in the third quarter, after growing 2.2% in the second quarter, with the first estimate subject to revision.

Personal consumption expenditures inflation was also expected to rise to 3.7% in September from 3.4% in August, according to the Associated Press. The Federal Reserve uses this measure as its preferred inflation gauge and targets a rate of 2%. The Federal Open Market Committee meeting is scheduled for October 27 and 28, with the Fed chair due to hold a news conference on October 28, according to the Federal Reserve's calendar. The meeting minutes are scheduled for release on November 18. These dates follow a week in which stocks rose, but continued concerns about borrowing and AI spending keep corporate results and the Fed decision in investors' focus.