A trending topic on X on 4 November read “Anthropic’s IPO Odds Drop on Polymarket Amid Huge Losses and Costs”. Anthropic’s amended IPO filing shows a net loss of $104.0 billion for the nine months to 30 September 2026.
By our arithmetic, 91% of that loss, $94.3 billion, is the change in fair value of convertible notes, derivative liabilities and SAFEs. The operating loss for the same nine months was $1.26 billion.
Business Pill · Gross Margin
An evergreen Business Engineer explainer on gross margin. It teaches the general idea only and does not discuss Anthropic.
Animated chart. Chart: FourWeekMBA.
The key insight: Anthropic’s S-1/A shows a $104.0 billion net loss for the first nine months of 2026; $94.3 billion of it, about 91% by our arithmetic, is the change in fair value of convertible notes, derivatives and SAFEs, against an operating loss of $1.26 billion.
The S-1/A, filed on SEC EDGAR on 2 November, reports nine-month 2026 revenue of $33,242 million and an operating loss of $1,260 million. The change in fair value line was a $94,324 million expense, and other income (expense), net was a $10,397 million expense.
The filing explains the fair-value line: the nine-month increase “was primarily driven by an increase in the fair value of our outstanding convertible promissory notes resulting from an increase in our enterprise valuation from 2025 to 2026”.
It adds that Anthropic “will continue to recognize changes in fair value until these instruments are converted into equity, repaid, or otherwise settled”. The cash flow statement adds the $94,324 million back as an adjustment to reconcile net loss to operating cash.
Operating income vs net loss by quarter, with the fair-value change on convertible notes, derivatives and SAFEs. Source: Anthropic, PBC Form S-1/A (SEC EDGAR, 2 Nov 2026). Shares and margins are our arithmetic.
What Was Posted on X
Revenue up eleven-fold and a $23 billion loss in the same quarter: Anthropic’s final pre-IPO numbers are as extreme as the hype around them.
Unusual Whales posted at 00:58Z on 4 November about the $23 billion third-quarter loss. By our arithmetic, the fair-value change on convertible notes, derivatives and SAFEs was about 94% of that quarter’s $23,291 million net loss, per the S-1/A.
Seven Quarters, Two Lines
The quarterly table runs from the first quarter of 2025 to the third quarter of 2026. The only quarter with operating income was the second quarter of 2026: $974 million on $11,555 million of revenue, an operating margin of about 8.4%, by our arithmetic. That quarter’s net loss was $66,309 million, of which $59,597 million was the fair-value change.
In the third quarter, revenue was $16,956 million and the operating loss was $567 million, a margin of about minus 3.3%, by our arithmetic. The net loss was $23,291 million; the fair-value change, $21,936 million, was about 94% of it, by our arithmetic.
Across all seven quarters, the fair-value change totals $128.6 billion, about 88% of the combined $146.0 billion net loss, by our arithmetic. Combined, the seven quarters show a net operating loss of $9.3 billion, by our arithmetic.
Where the Costs Are
The costs side is in the operating lines. Compute and infrastructure was $9,863 million in the third quarter, about 58% of revenue, up from about 48% in the second quarter, by our arithmetic.
The filing attributes the third-quarter operating loss to “$5.0 billion of compute under short-term commitments, which currently costs significantly more than comparable compute procured under our multi-year commitments” and “$2.0 billion of non-cash charges related to our donation matching program”.
The Cash Line
Net cash provided by operating activities was $6,569 million for the nine months, against $2,024 million used a year earlier. Investing activities used $36,546 million and financing activities provided $110,735 million in the same period.
The filing also warns that the company expects its investments “to result in significant net cash used in operating and investing activities for the foreseeable future”.
As we read the filing, the loss line and the operating line describe different things: the fair-value line moves with the enterprise valuation behind the convertible notes, while compute, personnel and sales costs sit in the operating line.
As we read the filing, the cost pressure in the third quarter is in compute: compute and infrastructure rose to about 58% of revenue from about 48% a quarter earlier, by our arithmetic, with $5.0 billion of short-term compute named as the main driver.
Anthropic, PBC, Form S-1/A, 2 Nov 2026
“We will continue to recognize changes in fair value until these instruments are converted into equity, repaid, or otherwise settled”
Three Implications
FOR THE LOSS HEADLINE Across seven quarters, the fair-value change is about 88% of the combined $146.0 billion net loss, by our arithmetic.
FOR THE OPERATING LINE The second quarter of 2026 had operating income of $974 million; the third quarter had an operating loss of $567 million on $16,956 million of revenue.
FOR CASH Operating activities provided $6,569 million in the nine months, while investing activities used $36,546 million, according to the filing.
The framework says: “The new job of finance is to manage the ratio between the two — work produced per token burned.”
As we read it, Anthropic’s operating line is where that ratio shows up, in compute cost as a share of revenue. The framework predates this filing and does not discuss Anthropic’s S-1/A.
We could not load Polymarket’s market pages from our location on 4 November, so we do not cite a probability or a change in odds. The quarterly figures are unaudited. The filing does not say what the fair-value line will be after the offering, and we make no prediction about the IPO.
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Anthropic’s S-1/A shows a $104.0 billion net loss for the first nine months of 2026, of which $94.3 billion, about 91% by our arithmetic, is the change in fair value of convertible notes, derivatives and SAFEs. The operating loss was $1.26 billion, and operating cash flow was $6.6 billion positive.
A note on sourcing. All financial figures come from Anthropic, PBC’s Form S-1/A (Amendment No. 1), filed on SEC EDGAR on 2 November 2026; quarterly figures are unaudited. Shares, margins and totals across quarters are our arithmetic. The X trend title is quoted as it appeared; no prediction-market price is cited.
Gennaro Cuofano is a CRO and tech executive who has worked in AI since late 2015, starting with bringing NLP, natural-language generation, voice and chatbot products to the marketing industry. His background is in law and finance: he holds a Master's degree in Law and an International MBA with an emphasis on corporate finance (LUISS Business School and the University of San Diego, 2012), and worked as a financial analyst at a real-estate investment firm in San Diego and as an assistant controller. His work focuses on business model strategy, business engineering and, more broadly, structural analysis: how companies make money, read from their own filings. He created FourWeekMBA and leads research there and at The Business Engineer, his newsletter on AI and business strategy, with over 95,000 subscribers and more than 1,000 published analyses. His writing has also appeared on Entrepreneur (for example, How to Digitize a Family Business in Europe) and HackerNoon. Find him on LinkedIn and Substack. See how we source.
