Anthropic's S-1, explained: what it shows and when the IPO could come

On October 26, 2026, Anthropic published its S-1, the registration statement for its initial public offering. It had been in confidential review with the SEC since June 1 and had filed five revised drafts along the way. The public version runs to more than 300 pages plus financial statements. This piece goes through what it shows, what the coverage since has focused on, and what the filing and SEC rules say about when the shares could start trading.

The short version

Ticker and venue: Class A shares on the Nasdaq Global Select Market under the symbol ANT, with Goldman Sachs and Morgan Stanley leading 22 banks.
Still blank: the price range, the number of shares and the date. They come in an amended S-1, which also has to add third-quarter results.
Growth: revenue of $16.29 billion in the first half of 2026, about 14 times the $1.16 billion of a year earlier.
Profit: a first GAAP operating profit, $974 million, in the second quarter of 2026. The net loss of $80.75 billion for the half is mostly a non-cash charge on convertible notes.
Compute: contract-by-contract commitments that outlets have added up to anywhere from about $420 billion to more than $650 billion, most of it non-cancellable.
Control: a single share held by the seven co-founders carries 50.1% of the votes, and the Long-Term Benefit Trust elects a majority of the board. Public investors buy the class with the least say.
Timing: SEC rules put the earliest roadshow start at November 10. Reports point to trading before Thanksgiving on November 26, with early December as the fallback.

What Anthropic actually filed

An S-1 is the document the SEC has to declare effective before a company can sell shares to the public. Anthropic used the confidential route: it submitted a draft on June 1 and amended it in July, August, September and twice in early October, out of public view. Publishing the S-1 made all of those drafts public too.

The public filing is complete on the business, the risks, the governance and the financial statements: audited for 2023 to 2025, unaudited for the interim periods to June 30, 2026. It is deliberately incomplete on the deal: every price, share count and offering size is a blank. The summary already refers to revenue “for the three months ended September 30, 2026” with the number left out, a sign that the next amendment will bring the third quarter.

The numbers

	2024	2025	H1 2025	H1 2026
Revenue	$386M	$4.59B	$1.16B	$16.29B
Compute and infrastructure	$2.52B	$7.33B	$2.33B	$8.95B
Operating loss	$2.98B	$8.06B	$2.14B	$693M
Adjusted operating result (non-GAAP)	-$2.79B	-$4.85B	-$1.85B	+$1.62B
Net loss	$8.31B	$41.97B	$12.97B	$80.75B

Source: Anthropic S-1, October 26, 2026. Adjusted figures leave out stock-based compensation, non-cash charitable contributions and the $1.5 billion Bartz settlement.

Three things stand out.

The growth is real, and it is slowing from an extreme pace. Quarterly revenue went from $376 million in the first quarter of 2025 to $11.56 billion in the second quarter of 2026. Bloomberg reported in October that Anthropic told prospective investors the third quarter came to $16.8 billion. That would be about 45% more than the second quarter: an enormous number, but well below the roughly two-and-a-half-fold jump of the quarter before. The Information reported that the deceleration had some investors arguing for a lower IPO valuation.

The operating business has turned the corner. Compute and infrastructure fell from 251% of revenue in early 2025 to 48% in the second quarter of 2026, because revenue grew faster than the capacity Anthropic had already bought. That produced the first quarterly operating profit. Fortune worked out roughly $3.45 billion of free cash flow for the first half. The Wall Street Journal pointed out how much the adjusted measure leaves out: stock-based compensation alone was $2.2 billion in the half.

The net loss is mostly an accounting effect. Anthropic raised money partly through convertible notes, mainly from Amazon. As the company’s valuation rose, the value of those notes rose with it, and that change runs through the income statement: $34.3 billion in 2025 and $72.4 billion in the first half of 2026. No cash left the company. Most of the notes convert into shares at the IPO; any that would take Amazon above its 12% ownership cap stay outstanding and keep being revalued until they convert.

The balance sheet is strong for now: $131.7 billion of cash and short-term investments at June 30, out of $141.1 billion raised since 2021.

Compute: the number everyone is trying to add up

The biggest open question in the coverage is the size of Anthropic’s compute bill. The S-1 describes each major contract but leaves the total blank. The named commitments include:

Google: at least $114.5 billion through July 2033, plus an estimated $125 billion to $150 billion of further TPU capacity in 2028 to 2031.
Amazon: at least $110 billion through April 2036.
Broadcom equipment leases: about $161.2 billion of rent on TPU-based hardware. The Wall Street Journal reported that banks, Blackstone and Broadcom formed a $63 billion vehicle to buy that equipment.
SpaceX’s AI unit: up to $120.5 billion into 2029, about $3.1 billion a month once all capacity is live, and cancellable on 90 days’ notice after early 2027.
Microsoft: at least $44.9 billion from November 2026 to May 2033.
Nscale, Lambda and AMD: up to about $44.6 billion, about $41.3 billion, and more than $20 billion respectively.

Depending on which contracts are counted, Bloomberg arrived at $417 billion of uncancellable spending and Fortune at $657 billion in total, of which $498 billion cannot be cancelled. All of these are larger than any revenue Anthropic has reported, which is the point of the bear case: the contracts do not shrink if growth slows. The bull case is the trend in the table above, where revenue has repeatedly outrun the capacity Anthropic secured.

There are early signs of strain at the edges. On October 28, Bloomberg reported that banks had shelved a bond sale tied to a $15 billion loan for an Anthropic-linked data center in Texas after state regulators paused new projects over grid concerns.

Customers: broad, sticky, and tied to the latest model

The filing counts more than 11,900 customers paying at least $100,000 a year, up from about 950 a year earlier, more than 1,900 paying $1 million and about 250 paying $10 million. Net revenue retention, which measures how much existing customers expand, was about 900%.

Concentration has eased. Two customers each brought in 12% of 2025 revenue; in the first nine months of 2026 none passed 10%, though the top five still made up about 25%. Two other disclosures got less attention than they deserve:

Model versions released in the previous six months made up more than 80% of third-quarter revenue. Anthropic’s revenue depends on staying at the frontier, release after release.
Anthropic estimates that 5% to 7% of revenue in the first nine months of 2026 came from customers it later found to be breaking its usage policy or terms, and expects that share to fall.

Competition is the other side of this. The Information reported that steep OpenAI discounts had won over some startup customers. Bloomberg focused on the tangle with Amazon, Google and Microsoft, which are at once investors, cloud suppliers, sales channels and rivals.

Who is in charge after the IPO

The governance section is where the S-1 is most unusual, and CNBC and TechCrunch both led with it. There are five classes of stock:

Class A, what the public buys: one vote per share. All Class A holders together can never have more than 49.9% of the vote.
Class F, a single share held by a company owned by the seven co-founders: 50.1% of the votes on ordinary shareholder matters, and no economic rights.
Class T, held by the Long-Term Benefit Trust: elects a majority of the board, no other vote, no economic rights.
Class N, held mostly by strategic partners such as Amazon and Google: full economics, no vote.
Class E, for employees other than the co-founders: votes on a few limited matters only.

The result is a “controlled company” under Nasdaq rules, and a structure in which outside shareholders cannot force a sale or replace the board. Anthropic argues that this protects its public benefit purpose. It also builds in dilution for its own mission: 5% of the fully diluted shares already sit in an Anthropic Public Benefit Fund, and the board may add up to 2% more each time the share price rises 50% above the previous milestone, starting from the IPO price. Each of the co-founders has pledged to give 80% of their Anthropic equity to charity.

When could the shares start trading?

Anthropic has not given a date, but the filing and two SEC rules narrow the window.

The 15-day rule. A company that filed confidentially must publish its S-1 at least 15 days before its roadshow. From October 26, that makes November 10 the earliest start. Bloomberg reported in early October that the roadshow could begin as soon as the week of November 9.
The 135-day rule. Under Regulation S-X Rule 3-12, a filer of Anthropic’s status cannot go effective with financial statements that are 135 days old or more. The S-1’s statements end on June 30, which puts that line at November 12. Since pricing before then is not realistic, an amendment with figures to September 30 has to come first. The Wall Street Journal reported in September that the debut was pushed into November so the offering could include the third quarter.
The roadshow itself. For a large IPO it typically runs one to two weeks. The price range is published in an amendment as it starts, and the final price is set the evening before the first trade.
Thanksgiving. US markets are closed on November 26 and close early the next day, and large deals rarely price that week.

Put together, that gives three scenarios. These are our reading, not company guidance:

On schedule: amendment with the price range in early November, roadshow from about November 10, pricing and first trade in the second half of November, before Thanksgiving. This is what the reporting describes.
A short slip: SEC comments or a weak market push the roadshow back a week or two, and the shares price in early December, before the year-end slowdown.
A longer delay: a sharp market fall or a problem in the review pushes the deal into 2027. The September 30 figures would then go stale in mid-February, so a delay past that would mean adding full-year 2026 results.

Washington adds attention but no formal obstacle. On the day of the filing the FTC demanded testimony from Anthropic executives in its probe of AI safety risks, and on October 28 The Wall Street Journal reported that Senator Elizabeth Warren was demanding answers about the existential risks the S-1 discloses. Neither has, so far, moved the reported schedule.

What could it be worth?

Reports have described a target of around $2 trillion, roughly double the $965 billion Series H in May, with others pointing to $1.5 trillion after growth slowed. The amended S-1’s price range will be the first figure Anthropic itself puts on the shares.

The filing allows some rough arithmetic. Anthropic says the 846.8 million shares it put into its Public Benefit Fund were 5% of its fully diluted shares at June 30, which implies about 16.9 billion shares in total. On that base, a $1.5 trillion valuation works out to roughly $89 a share and $2 trillion to roughly $118. For comparison, the Series H price of about $589 per preferred share converts into ten common shares after the September ten-for-one split, about $58.90 each. Treat these as orders of magnitude: the IPO adds new shares, and the real count will be in the amendment.

CNBC noted that a weak debut could weigh on the whole technology sector, and The Wall Street Journal that even Anthropic’s rivals are hoping it goes well, since it sets the yardstick for every private AI lab that wants to follow.

After the listing: a staggered lock-up

Instead of the usual 180-day ban followed by a flood of selling, Anthropic has negotiated a schedule that releases shares in steps. Employees and non-founder officers can sell up to 10% from the first day of trading and another 35% after the full-year 2026 results. Large holders are released in small tranches from day 27, with some spread over a full year. The co-founders are locked up for up to a year, with 29% free after six months or the first-quarter 2027 results. The upshot for buyers is steady new supply rather than one big cliff.

Can you buy at the IPO price?

Possibly, and more easily than in most large offerings. Bloomberg reported that Anthropic is weighing setting aside 15% to 20% of the shares for individual investors, with JPMorgan leading US retail sales and Citigroup the international retail offering. The S-1 confirms public offerings in Australia, Canada, Japan, Switzerland, the UK and some countries of the European Economic Area, including a European retail offering under a separate European prospectus. It does not say which countries, and no broker has announced an allocation yet. Demand will far exceed what is set aside, so expect small fills if any. From the first trade, anyone with a broker that offers Nasdaq stocks can buy ANT at the market price; our how to buy guide covers both routes.

What to watch next

The amended S-1: third-quarter results, the price range and the number of shares.
The split between new shares and shares sold by existing holders, which shows how much money goes to Anthropic.
Which brokers, in the US and in Europe, get a retail allocation.
Whether the roadshow starts in the week of November 9, as reported.
Any response to the FTC and to Senator Warren.

We track every step on our IPO page.

This is analysis, not investment advice. See our disclaimer.