Anthropic's S-1 Shows Half Its Big Spenders Locked Into Two Products

More than half of Anthropic's customers spending at least $100,000 a year now use both the Claude platform and a first-party app such as Claude Code or Cowork, up from roughly 30% at the end of last year. That figure, disclosed in the company's S-1 filed with the Securities and Exchange Commission on Monday, is the clearest signal yet that Anthropic is replicating the cross-product stickiness that made Amazon and Uber hard to leave.

"The speed and depth of our enterprise customer adoption are powerful evidence of Claude's position at the frontier of AI," the filing reads.

How big is the customer base?

As of September 30, the numbers break down cleanly:

• More than 11,900 customers spending at least $100,000 annually
• More than 1,900 customers spending over $1 million
• Roughly 250 customers spending $10 million or more per year

Anthropic attributes the momentum to "significant usage expansion as customers realize the value of deploying Claude across their organizations." That expansion drove net revenue retention of about 900% as of the end of the third quarter. In plain words: existing customers spent roughly nine times what they spent a year earlier.

Why does the two-product number matter?

The S-1 takes a direct shot at legacy software vendors. Anthropic pitches Claude not as a "static product that serves a single use case" but as "frontier AI with rapidly advancing capabilities" spanning three layers: the models, the developer platform, and the applications users touch directly.

"An advance at any layer compounds across all three layers, accelerating the pace at which we can deliver more capable intelligence," the filing reads. Anthropic calls this "integrated approach" the reason more customers now use both the Claude Platform and its first-party apps.

The playbook is familiar. Uber started with rides, then pushed into food delivery and freight. Amazon pulled customers into AWS with cloud computing, then expanded into storage, databases and more — each step making the ecosystem harder to exit. Anthropic doesn't need to sell each product to a new buyer: a business that starts with the API can hand Claude Code to its engineers, then roll Cowork out to the broader workforce.

Those app users become far more valuable. In the third quarter, the highest-spending 5% of Claude Enterprise customers who used Claude Code spent about 20 times as much per month as the average enterprise user who didn't touch the coding tool, per the filing. The gap shows how much room per-user spend still has to grow — and why Anthropic wants its apps inside every account that starts on the API.

How does Anthropic accelerate the land-and-expand?

The company amplifies organic diffusion by investing in Applied AI teams. One internal team works with startups and enterprises to place Claude inside customers' existing technology stacks. Separately, Anthropic recently launched Ode with Anthropic, a venture with Blackstone and other private equity firms that embeds forward-deployed engineers into businesses to build bespoke tools on Claude.

Distribution also runs through hyperscalers. Under a "joint go-to-market approach" with AWS, Google Cloud, and Microsoft Azure, Anthropic keeps the direct contractual relationship with customers and pays each cloud provider a fee — an arrangement the company says lets it "avoid channel conflict" and "set pricing."

What could break the model?

The filing flags real headwinds despite first-half 2026 revenue of $16.3 billion, up from $1.2 billion in the same period last year. The same cloud partners that sell Claude increasingly see Anthropic as a competitor, which could make it harder to secure compute. Amazon, Google, and Microsoft may prioritize their own requirements or rivals they've invested in, the filing states.

Customer concentration is the other stated risk. "A significant reduction in spending by, or the loss of, one or more of our largest customers, if not offset by new customer relationships or increased business from our other existing customers, could adversely affect our business, financial condition, and results of operations," the risk factors read.

Anthropic says it intends to "reinvent our business" by releasing "new classes of products whose aim is to dwarf the economic value of our existing ones" — devoting less effort than a typical business to "entrenching our current products and business models, and more effort to defining new ones." Whether the ecosystem flywheel spins fast enough to outrun its own dependence on cloud rivals is now the question investors will price.