S&P 500 rises 0.7% as Anthropic files IPO paperwork
Key Facts
The S&P 500 rose 0.7% to 7,676.77 on Monday, October 26, 2026, and the Nasdaq Composite gained 0.8% to 26,169.38. The gains came on the day Anthropic filed registration documents for an initial public offering, putting AI spending plans and valuations of AI companies to a new test in the market. The company said in its filing that it intends to list its shares on the Nasdaq Global Select Market under the symbol ANT. Trading has not begun, and the filing did not specify the offering amount or final valuation. Reuters put the company’s value at about $1.5 trillion among some current and potential investors, compared with about $2 trillion a week earlier, but those figures are circulating estimates, not targets announced by the company.
The advance extended to other indexes, with the Dow Jones rising 0.3% to 52,361.58 and the Russell 2000 gaining 0.4% to 2,786.42. In morning trading, Reuters reported that major indexes were higher and U.S. stock futures briefly got a boost after Anthropic’s filing was published. The S&P 500 was up 0.5% at the time, before closing with a gain of 0.7%. The market move was accompanied by a decline in the yield on the 10-year U.S. Treasury note to 4.98%, from 5.00% at Friday’s close. The yield had exceeded 5.30% earlier in October, making its level on Monday the lowest since that peak earlier in the month.
Investors are focused on corporate earnings this week, with The Associated Press saying earnings reports are due from nearly one-third of S&P 500 companies. The timing adds significance to Anthropic’s filing, as the company reports rapid revenue growth alongside large losses. Revenue topped $16 billion in the first half of 2026, 14 times revenue in the same period a year earlier. By contrast, it recorded a net loss of $80.7 billion in the first half. The loss included a one-time accounting item of $72.4 billion related to changes to financing agreements, while the loss in the corresponding period of 2025 was about $13 billion.
Founded in 2021 by former OpenAI executives, Anthropic competes, according to The Associated Press, with OpenAI and startups in the United States and China, as well as SpaceX’s AI business. Its move toward the public market comes as Reuters says market volatility has weakened the autumn IPO calendar. Higher borrowing costs have also heightened investor concerns about the debt-funded AI investment boom. Peter Andersen, founder of Andersen Capital Management, said the IPO’s outcome “will be a significant indication of investor sentiment toward continuing to support capital spending on AI development.” The offering’s performance, once its terms are set and trading begins, could therefore signal investors’ willingness to fund that spending, while circulating valuation estimates remain separate from any final price the company has not announced.
The Federal Reserve meeting adds to this week’s events: the Federal Open Market Committee meets on October 27 and 28, 2026, with the press conference scheduled for October 28. Microsoft is also scheduled to report first-quarter fiscal 2027 results on October 28. These events follow a session of gains for U.S. indexes, as investors await corporate earnings and the central bank’s decision. The available facts do not establish a specific interest-rate expectation, so the market move cannot be attributed to expectations that the rate would remain at a particular level. Anthropic’s offering terms, size and final valuation were not included in the company’s filing, which announced a planned listing under the symbol ANT.