Over 80% of Anthropic’s Q3 revenue came from new models

Anthropic’s S-1, filed on October 26 ahead of a Nasdaq listing under the ticker ANT, says model versions released in the six months to September 30 brought in over 80% of its third-quarter revenue, a figure The New Stack picked out of the filing. If your team reads that as a count of customers who switched to new models, it measures something else: dollars, as a share of total quarterly revenue. And the filing’s customer figures show those dollars spreading out, with about 79% of Q3 revenue coming from customers outside the top five, up from about 64% in Q1 2026.

The filing gives the figure as an example of volatility. Anthropic writes that customer usage is shaped by “the frequency and capability of new model version releases, as well as seasonal trends,” which can make results swing from period to period, and goes on:

For example, model versions released in the six months ended September 30, 2026 accounted for over 80% of our revenue for the three months ended September 30, 2026.

Which releases count

The New Stack counts eight widely available Claude models plus three restricted-access Mythos models shipped between April and September. That tally is the outlet’s own. The S-1 names Mythos Preview in April, Fable 5 reaching general availability alongside Mythos 5 in June, and Mythos 5.1, Fable 5.1 and Opus 5.5 in September. Launches from late September had only days to add to the quarter, and revenue per model is not disclosed.

Two of those models went dark for a stretch inside the window. In June the Commerce Department imposed worldwide export restrictions on Fable 5 and Mythos 5, and Anthropic disabled both for every customer, foreign or domestic, re-deploying them after it updated its safeguards. Access to its other models was unaffected.

Opus 5.5 is the one release the filing ties directly to customers moving. Anthropic says it “delivered a significant increase in capability and a lower cost per task compared to previously available models, and many customers have since migrated to it from older models.” The New Stack treats migration as an open question; on Opus 5.5 the company states it outright, though without a number. There is a precedent in the same document: after the Opus 5 launch, quarter-over-quarter revenue growth went from 48% in Q4 2025 to 132% in Q1 2026, and both rates check out against the quarterly table.

Dollars or customers?

The New Stack’s caution is that a small group spending heavily on the newest releases could account for much of that 80%. At the customer level, the filing’s concentration figures point the other way. The top five customers made up about 21% of Q3 revenue, against about 36% in Q1, and roughly 25% across the first nine months of 2026; no single customer passed 10%. Net revenue retention, what existing customers spend now against what they spent a year earlier, stood at about 900% as of September 30. None of these figures is broken down by model, so they narrow the outlet’s point without settling it.

Spending per user does vary widely. In Q3, Claude Enterprise users who did not use Claude Code averaged under $75 a month, while the top 5% of Enterprise users who did use it spent about 20 times that. The New Stack’s version, heaviest Claude Code users against “other enterprise users,” is looser than the groups the filing actually compares.

Does revenue fund the next model?

Anthropic says in the filing that it relies on growing revenue to pay for the research, compute and talent behind more capable models, which then draw more spending. It does not say whether that spending is what sped up its 2026 release pace. And its compute bill does not move with a single quarter’s demand: Anthropic typically buys compute 12 to 18 months before it becomes available, so the expense is “generally fixed in the near term” and rose “as committed compute became available to us rather than in response to in-period demand.” That is the company’s account of how it buys capacity, not something we measured.

The ratio shifted all the same. Compute and infrastructure fell from 251% of revenue in Q1 2025 to 48% in Q2 2026. In Q2, Anthropic spent $5,558 million on compute against $11,555 million in revenue, which works out to the $2.08 of revenue per compute dollar that Fortune reported; by our arithmetic from the same table, it was $0.40 in Q1 2025 and $1.40 in Q1 2026. Q2 2026 was also the only quarter of operating profit among the six in the filing, at $974 million.