Anthropic Opens Its Books in Public S-1: $16.3 Billion of First-Half Revenue and an $80.7 Billion Net Loss

Anthropic, PBC filed a public registration statement on Form S-1 on Monday, opening the Claude maker's finances to public investors for the first time and applying to list its Class A common stock on the Nasdaq Global Select Market under the symbol ANT.

The filing is a preliminary prospectus, subject to completion, and the blanks are part of the story. Anthropic is offering Class A common stock itself, with additional shares sold by selling stockholders, but the share counts and the estimated price range are left blank in this version, and the company will receive no proceeds from the selling stockholders' shares. Goldman Sachs & Co. LLC, Morgan Stanley and J.P. Morgan head the underwriter list on the cover, followed by Citigroup, Barclays, Wells Fargo Securities, BofA Securities and others. The stated use of proceeds is general corporate purposes — working capital, operating expenses and capital spending including compute and infrastructure, hiring and retention, and possible acquisitions, none agreed — plus tax withholding tied to settling restricted stock units. Nothing in the document prices the deal, and the stock is not yet trading.

Revenue multiplied while the operating loss narrowed

The growth curve is the reason this filing will be read far beyond the syndicate desk. Revenue was $41 million in 2023, $386 million in 2024 and $4.59 billion in 2025, then $16.29 billion in the first half of 2026 alone — against $1.16 billion in the first half of 2025. The filing says revenue grew 1,368% year over year in the three months ended June 30, 2026, while compute and infrastructure expense grew 300%, and it puts net revenue retention at approximately 900% as of September 30, 2026. Trailing revenue per employee was over $6.6 million as of September 30, 2026, up from $1.4 million a year earlier. The reported operating loss narrowed to $693 million in the first half of 2026 from $2.14 billion a year earlier, even as total operating expenses reached $16.98 billion.

The $80.7 billion loss is mostly a valuation mark

The headline net loss requires the filing's own explanation. Anthropic reported a net loss of $80.75 billion in the first half of 2026, after $41.97 billion in 2025 and $8.31 billion in 2024. The driver was not operations: the non-cash change in fair value of convertible notes, derivative liabilities and SAFEs was a $72.39 billion charge in the first half of 2026 and $34.31 billion in 2025, which the filing says was primarily driven by increases in the company's enterprise valuation, and those instruments convert at the offering. On the company's adjusted measures, which strip out those marks, the picture reverses: adjusted operating income was $1.62 billion in the first half of 2026, an adjusted operating margin of 10% against a reported operating margin of -4%, after an adjusted operating loss of $4.85 billion in 2025, and adjusted net income was $2.67 billion in the first half of 2026. Reported and adjusted figures describe the same company; they answer different questions, and they are kept separate on every line here.

Reuters, reporting on the filing on Monday, confirmed the same shape — first-half revenue of about $16.3 billion and a net loss of about $80.7 billion driven by the convertible fair-value marks. Separately, Reuters reported that some investors now value the company at about $1.5 trillion, down from roughly $2 trillion, and that at an October 14 investor event the company said third-quarter revenue rose to $16.8 billion and it was profitable on an adjusted basis in the third quarter. Those figures are reported context, not S-1 data: the filing's tables run through June 30, 2026, and its third-quarter revenue figure is blank.

Compute ate the growth, and the balance sheet funded it

The cost side is a compute story. Compute and infrastructure expense was $8.95 billion in the first half of 2026 — more than the $7.33 billion spent in all of 2025 — alongside personnel costs of $3.15 billion, including $2.2 billion of stock compensation, sales, marketing and partnerships spending of $3.17 billion and other operating costs of $1.71 billion. The prior year carried a $1.5 billion Bartz settlement line that did not repeat. Distribution runs through the same companies that supply the machines: revenue through cloud provider marketplaces was about 47% of 2025 revenue and about 48% in the first half of 2026, the top five customers accounted for about 25% of revenue for the nine months ended September 30, 2026 with no single customer above 10%, and the supply base spans AWS Trainium, Google TPUs, NVIDIA GPUs and AMD GPUs. Claude Opus 5.5 cut customer cost per task by about 40% compared with Opus 5 — the efficiency claim the cost curve depends on.

Cash is not the near-term constraint. Operating cash flow turned positive at $3.93 billion in the first half of 2026, the first positive period shown, after −$2.64 billion in 2025, while investing used $17.18 billion and financing provided $110.77 billion. At June 30, 2026, Anthropic held $112.39 billion of cash and equivalents and $19.26 billion of short-term investments — $131.65 billion combined — against total assets of $147.36 billion, and had raised an aggregate of $141.1 billion of capital as of that date. What the filing does not size is the future bill: aggregate committed spend is stated as 'more than $' with the amount left blank in this preliminary prospectus, substantially all of it for compute and infrastructure, spanning periods to 2045. Any commitment total circulating elsewhere is not confirmed by this document.

Control stays with the trust and the founders

Anthropic is a Delaware public benefit corporation, and its stated public benefit is the responsible development and maintenance of advanced AI for the long-term benefit of humanity. The governance structure insulates that mission — and control — from ordinary shareholder pressure. The Long-Term Benefit Trust holds the single Class T share and elects and removes the Class T directors, who will constitute a majority of the board; Class T carries no economic rights and no general voting rights. A founder limited liability company whose initial sole members are the seven co-founders will hold the single Class F share, carrying 50.1% of total voting power on matters generally submitted to stockholders, including electing the non-Class T directors, with no economic rights. Class A stock, the class being sold, carries one vote per share; Class N is non-voting, held primarily by strategic partners, and generally converts to Class A on transfer to an unaffiliated party; Class E, for employees other than the co-founders, has limited votes, no economics and zero shares outstanding after the offering. The company describes itself as a Nasdaq controlled company. A 10-for-1 forward split of Class A and Class N took effect on September 17, 2026, with share figures retroactively adjusted, alongside a 1-for-1,000 reverse split of Class T. Founded in 2021 and headquartered at 548 Market Street in San Francisco, the company is led by co-founders Dario Amodei as chief executive and Daniela Amodei as president and chair.

What remains unknown

Almost everything that would let an investor price this company is still blank. The final share counts, the price range and therefore the valuation are not in this filing; the commitment total is blank; third-quarter data beyond the reported investor-event context is not in the tables. What to watch is specific: Securities and Exchange Commission review, an amended filing that fills in the share counts and price range, and the reported roadshow timing that would follow. Until an amendment lands, the verified record is the filing itself — explosive reported growth, a first half of adjusted operating profit, a paper loss created by the company's own rising valuation, and a control structure designed so public shareholders fund the mission without steering it.