Anthropic’s IPO Filing: A Revenue Rocket Strapped to a $430 Billion Bill It Can’t Cancel

Anthropic’s public IPO filing shows one of the fastest-growing companies ever to approach the stock market. It also shows a compute bill measured in hundreds of billions of dollars, much of it fixed, arriving just as growth starts to cool.

The company behind the Claude models filed its S-1 with the SEC on October 26. It plans to list on the Nasdaq Global Select Market under the ticker ANT. The price range and share count are still blank, so the valuation is not set yet.

The question for investors is simple to state and hard to answer: can revenue keep growing fast enough to pay for the computing power Anthropic has already signed for?

Revenue: from $376 million to $16.8 billion a quarter

Revenue for the first half of 2026 was $16.29 billion, against $1.16 billion in the same period of 2025. The second quarter alone brought in $11.56 billion. Anthropic later told investors that third-quarter revenue was about $16.8 billion, a figure that is not yet audited.

Q3 2026 is the unaudited figure Anthropic gave investors in October

Show the numbers

	Revenue
Q1 ’25	$0.38bn
Q2 ’25	$0.79bn
Q3 ’25	$1.38bn
Q4 ’25	$2.04bn
Q1 ’26	$4.73bn
Q2 ’26	$11.56bn
Q3 ’26	$16.8bn

Source: Anthropic S-1 (Q1 ’25–Q2 ’26); Q3 ’26 as reported by the Financial Times

The customer numbers are just as striking. Net revenue retention was about 900% as of September 30, meaning a typical existing customer was spending about nine times what it spent a year earlier. More than 11,900 customers pay at least $100,000 a year, up from about 950, and more than 1,900 pay over $1 million. Revenue per employee rose to $6.6 million from $1.4 million.

The growth curve is bending

Revenue rose 144% from the first to the second quarter of 2026, then about 45% from the second to the third. Q3 added roughly $5.2 billion of revenue, against $6.8 billion in Q2. That makes it the first quarter in the series to add fewer new dollars than the quarter before.

Some slowdown is normal: percentage growth shrinks as the base gets bigger, and the prospectus itself warns that growth may decline and fluctuate. Research firm SemiAnalysis puts Anthropic’s current annual run rate at about $74 billion, still enormous for a company that made about $4.6 billion in all of 2025.

The update was more mixed than the market’s negative reaction suggested.

— Gil Luria, D.A. Davidson, who attributes the slowdown to competition from OpenAI and open-weight models rather than weaker demand

One part of the slowdown was a choice. According to the Financial Times, Anthropic told investors that distillation, where rival AI labs use its models to train their own, had accounted for 5% to 7% of revenue, and that it cut this back materially in the third quarter.

The bill that doesn’t shrink with demand

The filing lists Anthropic’s biggest computing contracts one by one. Four of them can’t be cancelled except if a party defaults or the supplier commits an uncured material breach: about $161.2 billion of five-year equipment leases with Broadcom, at least about $114.5 billion with Google, at least $110 billion with Amazon and at least $44.9 billion with Microsoft. Together that is about $430.6 billion.

Committed amounts by supplier; Google, Amazon and Microsoft are minimums. Total ≈ $430.6bn

Show the numbers

	Commitment
Broadcom	$161.2bn
Google	$114.5bn
Amazon	$110bn
Microsoft	$44.9bn

Source: Anthropic S-1, as summarised by Cape Fear Advisors

Three more contracts have softer terms. SpaceXAI is up to $120.5 billion, but after initial periods ending in January and March 2027 either side can cancel on 90 days’ notice. Nscale is up to about $44.6 billion, with fees due only as capacity is delivered. Lambda is about $41.3 billion, and its largest part can be terminated if Lambda doesn’t secure the data-center lease. All seven together come to about $637 billion, but that total mixes minimums and maximums, and the filing leaves its own grand total blank.

The mismatch is in the terms. Anthropic’s revenue is mostly pay-as-you-go: the filing says it is “primarily consumption-based, and much of it is not subject to long-term contractual commitments.” Its biggest costs are the opposite. The S-1 also warns that the company “may enter into these obligations based on revenue expectations that may not be realized.”

A rough sense of scale

Third-quarter revenue of about $16.8 billion works out to roughly $67 billion a year. SpaceXAI alone is expected to cost about $3.1 billion a month once fully delivered, which Anthropic expects in December: about $37 billion a year. Spread evenly over five years, the Broadcom leases add about $32 billion a year.

Those two suppliers alone come to about $69 billion a year, close to the company’s entire current revenue rate, before Google, Amazon and Microsoft are counted. This is our own illustrative arithmetic, not a payment schedule: start dates and ramps differ, and the SpaceXAI contracts become cancellable in 2027. But it shows why revenue has to keep growing quickly for the contracts to pay off.

The bull case

• Efficiency has flipped. Compute and infrastructure costs fell from 251% of revenue in Q1 2025 to 48% in Q2 2026. In Q2, revenue grew 1,368% year over year while compute costs grew 300%.
• It already makes money at the operating line. Q2 2026 showed a $974 million operating profit. For Q3, Anthropic told investors it had an 11% adjusted operating margin and positive cash flow, and the FT reported $1.70 of revenue for every $1 of compute.
• A large cash cushion. Cash and short-term investments were $131.7 billion at June 30, 2026.

The fine print

• The headline loss is mostly on paper. The first-half net loss was $80.7 billion, but $72.4 billion of it is a fair-value charge on convertible notes that rose with the company’s valuation. The operating loss was $693 million. The accumulated deficit is $132.9 billion.
• Revenue is booked gross. Sales through the Amazon, Google and Microsoft cloud marketplaces, about 48% of first-half revenue, count at the price the customer pays, with partner fees booked as costs. Sales, marketing and partnership costs rose from $120 million to $3.17 billion year over year.
• Q3 is not audited yet. The $16.8 billion figure comes from an investor update; the filing states Q3 only as a multiple of Q4 2024 revenue.

What to watch before ANT trades

• The amended filing: the price range, the share count and audited third-quarter numbers.
• Fourth-quarter growth: whether it holds near 45% or keeps slowing.
• The compute-to-revenue ratio as SpaceXAI capacity arrives in December and the other contracts ramp.
• What it means for the suppliers: these contracts are future revenue for Broadcom, Alphabet, Amazon and Microsoft, which makes Anthropic’s growth their story too.

The StockPizza take

Anthropic is a fast-growing business with improving margins and a large cash pile, tied to a computing bill that is mostly fixed. The growth and the profits are real. The IPO price will effectively be a bet on how long revenue keeps growing faster than that bill.