What a Wobbly AI Trade Means for Anthropic's IPO

TL;DR: Anthropic publicly filed its S-1 on Monday, starting the countdown on what Morningstar says is expected to be one of the largest IPOs on record. AI stocks have rebounded since, though Anthropic's sequential growth slowed to about 50% in the third quarter. Price is the open question.

Key Takeaways

• Anthropic's S-1 went public on Monday, per Morningstar.
• Compute costs rose 77% in the third quarter against 47% revenue growth, per the amended filing as relayed by Yahoo Finance.
• Odds of an IPO announcement before December fell to 57% on Nov. 6, per CNBC.

On Monday, Anthropic publicly filed its S-1 registration statement, according to Morningstar. That starts the clock on what is expected to be one of the largest initial public offerings on record. The same report says Anthropic's sequential growth slowed to about 50% in the third quarter.

The filing arrived after a rough stretch for AI stocks. The Morningstar US Artificial Intelligence Index rose 2.0% on Monday after the filing and another 2.5% on Tuesday, per the same Morningstar report.

How wobbly was the AI trade going into the filing?

Wobbly enough to move IPO odds. CNBC reported on Nov. 6 that the odds on Kalshi that Anthropic would announce an IPO before December fell to 57% from nearly 90% in a week. That same report has the Nasdaq Composite closing Thursday more than 10% below its most recent high, which is the line Wall Street treats as a correction.

Those odds are traders' guesses about timing, not the company's plans, though they do show how fast sentiment toward the listing swung. It swung hard.

What does the S-1 say about the business?

The growth is real, and so is the slowdown. Morningstar reports that the number of firms paying Anthropic $100,000 annually rose to 11,900 by the end of the third quarter, from about 950 a year earlier. Malik Ahmed Khan, senior technology equity analyst at Morningstar, called the S-1 "better than expected."

Costs are climbing too. According to Yahoo Finance, compute costs rose 77% in the third quarter against 47% revenue growth, as shown in the amended filing. The 47% and the "about 50%" above come from different reports and may not measure the same thing, so don't net one against the other.

Yahoo also relays that the S-1 reports net revenue retention of about 900%. Harrison Rolfes, senior analyst at PitchBook, expects that figure to shrink fast from a small base.

What could a $1.5 trillion price mean for buyers?

A price near the top of the discussed range leaves little room for error. Yahoo Finance reports that large investors want Anthropic priced at the low end of a $1.5 trillion to $2 trillion range. At $1.5 trillion, the company would trade near 43 times trailing sales.

History is not kind to that multiple. Fortune, as relayed by Yahoo Finance, reported that only 14 of 4,110 IPOs from 1980 to 2024 sold above 40 times trailing sales. Buyers of those 14 at the offer price trailed the broader market by an average 15.4% within three years. Small sample. It describes the past, not Anthropic.

Signal	What the source reports	Source
Growth	Sequential growth slowed to about 50% in Q3	Morningstar
Costs	Compute costs up 77% vs. 47% revenue growth	Yahoo Finance
Valuation talk	$1.5 trillion, about 43 times trailing sales	Yahoo Finance
IPO timing odds	57% for an announcement before December	CNBC

Costs are growing faster than revenue, and the valuation talk is rich. Neither fact settles the pricing question alone.

Could new equity supply weigh on the market?

It could. Ben Inker and John Pease, asset allocation leads at GMO, say "each 1% increase in equity supply has historically cut market value by roughly 4% over the next year," per Morningstar. They estimate that SpaceX lockup expirations, new equity from hyperscalers, and IPOs from Anthropic and OpenAI could lift supply by 5% or more over the next year.

That is one asset manager's estimate, nothing more. It does explain how a strong filing and a nervous market can sit side by side, with growth slowing, costs climbing and investors still arguing over the right price.

What this means for accredited investors

If you hold Anthropic exposure through a secondary platform, a special purpose vehicle (SPV) or a feeder fund, the public S-1 is the first document you can check that vehicle's claims against. Read the share-class terms, the fees stacked on top and the lockup that applies to you.

Our earlier read of what the S-1 still doesn't answer covers the open items. The Series H analysis shows how the private round set the starting point, and the report on the public filing covers the timeline. If midterm politics is part of your AI thesis, see what the 2026 midterms mean for your retirement money.

Downside first: a listing priced for perfection leaves the least cushion if AI spending slows again. Nothing here is a recommendation to buy or avoid the shares.

Common mistakes

The first is reading a one-week rebound as a verdict. Two strong index days after a correction say little about where the offering will price. The second is treating prediction-market odds as company guidance, when they only reflect what traders expect. The third is assuming the private mark carries over to the public price. The public offering sets its own number.

FAQ

What are the big 3 IPOs coming?

Anthropic is the one in registration, with its S-1 public since Monday, per Morningstar. Bob Peck of New York Angels expects OpenAI to list in 2027, per Yahoo Finance.

Can I buy OpenAI stock?

Not on a public exchange yet. Peck expects an OpenAI listing in 2027, per Yahoo Finance, and OpenAI has cut its funding target to $20 billion from $30 billion. Until it lists, access runs through private vehicles with their own fees.

Is Anthropic still going public soon?

Anthropic has filed its S-1 publicly, per Morningstar, which starts the countdown to a listing. Kalshi traders put the odds of an announcement before December at 57% on Nov. 6, per CNBC.

One thing to do today

Open Anthropic's filing list on EDGAR and read the share-class and lockup sections of the S-1. Then watch for the next amendment, which is where a price range would appear, and join the free AIN briefing if you want that follow-up in your inbox.

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