Anthropic completes IPO, validating AI model company valuations and lifting AI sector equities.

U.S. stocks opened higher Tuesday as renewed enthusiasm around Anthropic's planned IPO lifted technology shares, offsetting pressure from elevated Treasury yields. The S&P 500 rose 0.21% to 7,699.6, while the Nasdaq gained 0.31% to 26,904.6. The Dow slipped 0.13% to 51,416.96.

The main catalyst was fresh optimism around Anthropic, whose upcoming listing could value the Claude developer at more than $2 trillion. The IPO prospectus also lays out roughly $518 billion in future cloud and infrastructure commitments, reinforcing expectations that the AI capital-spending boom still has room to run.

Anthropic's potential debut has become one of the biggest technology stories of the year. The company could seek a valuation near $2 trillion and has been linked with a raise of as much as $100 billion, potentially making it one of the largest IPOs ever attempted. Reports suggest Nvidia could invest as much as $10 billion as an anchor investor. Anthropic has also shifted its timetable toward November, giving the company more time to present stronger financials before listing.

The prospectus revived the recent AI infrastructure trade. European technology stocks jumped sharply earlier in the session, with the STOXX 600 technology index gaining about 2.5%, while U.S. semiconductor shares also benefited from expectations of continued spending on compute, networking, and data centers.

The bullish tech move comes against a difficult macro backdrop. The U.S. 10-year Treasury yield remained around 5.21%, keeping borrowing costs high across the economy and increasing the discount rate applied to long-duration growth stocks—a particular headwind for AI companies, whose valuations depend heavily on expectations for profits years into the future.

The broader AI spending cycle remains powerful, with capital expenditure tied to artificial intelligence an increasingly important contributor to U.S. growth. Yet rising debt costs are beginning to pressure companies funding new data centers and infrastructure. This tension between AI growth and expensive financing has already begun to surface in credit markets, where companies such as Oracle and Meta have faced higher debt costs as hyperscalers borrow aggressively to fund expansion.