Clouds Bill 48% of Anthropic Revenue; It Keeps the Customer

Sales through cloud marketplaces made up approximately 48% of Anthropic’s revenue in the first half of 2026, up from approximately 11% in 2023, according to the Form S-1 Anthropic filed with the SEC on 26 October 2026. The filing books that revenue as Anthropic’s own.

Its accounting note says Anthropic is the principal in those sales, recognising revenue on a gross basis, because it “has a direct contractual relationship with customers, is primarily responsible for providing the intelligence service to customers, and establishes pricing”.

How the Clouds Fit In

The S-1 says Claude is sold through the AI service layers of the three major clouds, naming Amazon Bedrock, Gemini Enterprise Agent Platform and Microsoft Foundry. In those marketplace sales it describes the cloud service providers, or CSPs, as “acting as collection agents for the Company in these transactions”.

The risk factors describe the money flow: “These platforms bill end customers, collect payments on our behalf, and remit such amounts to us, net of applicable platform and other fees.”

The accounting note adds: “The CSPs in these arrangements do not obtain control of the Company’s intelligence service at any point prior to transfer to the customer.” The Business section says: “We establish a direct contractual relationship with the customer and offer customers the flexibility to purchase directly from us or through CSP marketplaces, and many customers utilize both channels.”

Source: Anthropic, PBC Form S-1, filed with the SEC on 26 October 2026, notes to the consolidated financial statements (concentrations). Six-month periods and 30 June 2026 unaudited.

Four Roles for the Same Companies

The clouds that bill for Claude also appear elsewhere in the filing. The concentration note says “Certain of the CSPs also hold the Company’s non-voting redeemable convertible preferred stock and convertible notes.” The risk factors say “Certain CSPs from which we obtain substantial compute also develop and offer their own AI models and related services.”

Source: Anthropic, PBC Form S-1, filed with the SEC on 26 October 2026. The filing names Amazon, Google and Microsoft as its CSPs elsewhere.

The filing draws the consequence itself: “As a result, our commercial relationships with these providers may not always be fully aligned with our long-term interests”.

Where the Dependence Shows

The risk factors say “Any change to, or termination of, one of our significant distribution relationships could adversely affect our business by disrupting customer access to our models, reducing usage, or increasing customer acquisition, onboarding, and migration costs.” Enterprise customers that buy through marketplaces add reliance on “the CSPs’ procurement, security, and billing workflows”, the filing says.

Connecting the Coverage

Our NRR piece reported the marketplace shares and the collection-agent wording. Our customers piece reported the top five customers at about 25% of revenue and named Amazon, Google and Microsoft as compute suppliers. Our S-1 piece covered the headline numbers. What is new here is the accounting: Anthropic counts cloud-billed sales as its own, as principal on a gross basis.

The Structural Read

As we read it, the clouds handle billing and collection for nearly half of revenue, and marketplace sales made up 58% of net receivables at 30 June 2026, so a large part of Anthropic’s cash collection runs through them.

The filing’s own wording places the customer with Anthropic: a direct contractual relationship, pricing set by Anthropic, and no point at which a CSP takes control of the service. As we read it, the cloud is the route and Anthropic is the seller.

As we read it, certain of the same CSPs also hold Anthropic’s non-voting preferred stock and convertible notes, the S-1 says. Separately, the S-1 says certain CSPs that supply its compute also develop their own AI models, and that as a result the relationships may not always be fully aligned with its long-term interests.

Three Implications

FOR ENTERPRISE BUYERS The S-1 says customers can buy directly or through CSP marketplaces and that many use both, with the contract held by Anthropic in either case.

FOR INVESTORS The filing says approximately 48% of first-half 2026 revenue and 58% of net receivables at 30 June 2026 came through CSP marketplaces; we found no fee rate paid to the clouds.

FOR CLOUD PROVIDERS The S-1 describes the CSPs as collection agents that do not obtain control of the service, and records the sales as Anthropic’s revenue on a gross basis.

The Business Engineer Lens

This story maps onto the Business Engineer framework The AI Supercycle.

The framework says each layer of the AI stack is commercialised by the one above it: “Models need a harness. Harnesses need distribution.”

As we read it, the S-1 shows Anthropic using the clouds for that distribution while keeping the customer contract, pricing and revenue recognition itself. The framework was published in June 2026 and does not discuss this filing.

What Is Not Established

We found no fee rate or revenue share paid to the clouds in the filing, and no split of marketplace revenue by cloud. The passages we read do not say which expense line holds the CSPs’ fees; the filing lists “payment processing and platform fees” among other operating and administrative expenses. The S-1 does not say how many customers buy through both channels.

The Bottom Line

Anthropic’s S-1 says approximately 48% of its first-half 2026 revenue came through cloud marketplaces, that the clouds bill and collect as its agents, and that Anthropic records the sales as principal on a gross basis because it holds the contract with the customer and sets the price.