Anthropic's $86B IPO Looms Over Crowded US Listing Window

Anthropic's public filing, expected to match or exceed SpaceX's record $86.2 billion raise, is compressing the US IPO calendar into a frantic dash before the Federal Reserve's September meeting and November midterm elections. The AI company's looming mega-deal has left smaller issuers and their backers struggling to secure attention from long-term investors and sovereign-wealth funds.

"It's going to be a very busy September, running into October," said Rob Stowe, head of Americas equity capital markets at Barclays, who expects a highly concentrated issuance window between Labor Day and the election.

The stakes are visible in precedent: in the month before SpaceX listed, 14 sizable companies rushed to market and posted a weighted average loss of 9.5 percent. This year's US IPOs have returned 5.6 percent on a weighted basis, trailing the S&P 500's 13 percent gain and the Nasdaq 100's 17 percent advance.

With Anthropic expected to absorb long-term investor and sovereign-wealth attention, issuers that miss the window risk being crowded out entirely — a dynamic that could push weaker deals into a market already punishing latecomers.

A Window Squeezed by the Fed and the Ballot Box

The usable window between Labor Day and the November midterms is already thin, and the Fed's mid-September rate decision has squeezed it further. Hotter-than-expected inflation data has added to the uncertainty, pushing more companies to list early rather than wait.

Citigroup's global equity capital markets co-head Doug Adams expects six or more companies to raise more than $1 billion each between Labor Day and the election. Many large issuers are weighing market timing, he said, focused "not just on what the market is doing, but when the right time is for the company."

The queue is substantial. Cloud-computing firm Nscale has joined Anthropic in the listing pipeline; smart-ring maker Oura Health Oy could launch a multibillion-dollar IPO as soon as next month; and private-backed temporary-power provider Aggreko Plc and solar-and-storage firm CoVolt Power Inc. both filed publicly in August, aiming to list before Anthropic. SoftBank's digital-infrastructure unit SB Energy plans to raise more than $5 billion, while Roark Capital's Inspire Brands Inc. may test the market before the election. Switch Inc. filed confidentially earlier this month after a July funding round that valued it near $50 billion.

AI's Gravity Pulls Capital Away From Everything Else

With AI the market's defining theme, capital is concentrating in a narrow set of sectors, making listings harder for companies outside the trend. "Non-thematic IPOs are harder to get done," said Eddie Molloy, Morgan Stanley's global equity capital markets co-head. "There's a huge amount of capital around broad AI-infrastructure themes and aerospace and defense. If you're a small or mid-sized issuer not tied to those trends, it's harder to attract buyer attention."

The crowding also suppresses smaller deals. "If a company is small, we'd advise more caution," said J.D. Moriarty, vice chairman and global technology equity capital markets head at Bank of America. "The probability of indifference is high because there are so many large deals to choose from."

Large listings have disappointed this year. Of 16 companies that raised $1 billion or more, the weighted average post-IPO gain is 4.2 percent, and six of the ten largest deals trade below their issue price. SpaceX has gained less than 5 percent since listing, while SK Hynix's record debut has been volatile — both tied to investors' shifting appetite for AI trades.

A Firmer Tape Offers a Narrow Opening

The recent stabilization provides some cover for issuers. The S&P 500 has rebounded 5.4 percent from its July low, and the Nasdaq 100 has climbed more than 8 percent over the same stretch, giving companies a basis to argue for listing now.

Biotech is showing signs of life. US biotech IPOs have averaged $329 million in 2026, the highest since 2018, according to Bloomberg Intelligence analysts Sam Fazeli and Cindy Wu, with the sector on pace for roughly 30 listings this year — a strong finish to the year.

The consensus among market participants is that September and October will bring a dense wave of listings before Anthropic takes the stage. But the window is narrow and competitive, and for issuers and underwriters alike, timing will decide which deals succeed and which get left behind.

This article is for informational purposes only and does not constitute investment advice.