After there had been widespread speculation that Anthropic had surpassed OpenAI in revenue, OpenAI had told employees that this might not be the case.
In an internal memo sent to staff at the start of Q2, OpenAI Chief Revenue Officer Denise Dresser pushed back on Anthropic’s widely-cited $30 billion revenue run-rate, arguing that the figure is inflated by accounting choices that make Anthropic look bigger than it is. “Their stated run rate is inflated,” the memo reads. “They use accounting treatment that makes revenue look bigger than it is, including grossing up rev share with Amazon and Google.” OpenAI’s analysis, Dresser wrote, suggests this overstates Anthropic’s run rate by roughly $8 billion — bringing the real figure closer to $22 billion.
The argument has teeth. As analysts have previously noted, Anthropic reports revenue from its cloud distribution partners — AWS, Microsoft Azure, and Google Cloud — on a gross basis, booking the full amount billed through those channels, including the cloud providers’ cut, as top-line revenue. OpenAI, by contrast, reports its Microsoft Azure revenue on a net basis, deducting the partner’s share before recognizing it. Both approaches are permissible under US GAAP. But they produce meaningfully different headlines for economically similar transactions. Dresser made precisely this point: “We report Microsoft revshare net, which is more in line with standards we would be held to as a public company.”
The memo comes at a sensitive moment. Ramp data tracking corporate payments across over 50,000 US businesses shows Anthropic closing fast on OpenAI in enterprise adoption — with some analysts projecting a customer-count crossover within months. Anthropic has also claimed 10x annual revenue growth versus OpenAI’s 3x, a trajectory that, if accurate on a comparable accounting basis, would represent a genuine competitive threat.
Dresser’s memo doesn’t concede any of that ground. Beyond the revenue accounting critique, she laid out a broader case for why OpenAI should not be rattled by Anthropic’s rise.
On messaging, she argued that Anthropic’s brand is built on fear. “Their story is built on fear, restriction, and the idea that a small group of elites should control AI,” the memo states — an echo of criticisms US AI Czar David Sacks has also levelled at the company. OpenAI’s “positive message,” she wrote, will win over time.
On infrastructure, Dresser pointed to what she framed as a structural handicap: Anthropic’s decision not to secure enough compute early. “Their strategic misstep to not acquire enough compute is showing up in the product,” she wrote, claiming customers experience it through throttling, weaker availability, and unreliable uptime. OpenAI, she argued, saw the “exponential compute curve earlier, acted on it faster,” and now holds a durable structural advantage.
On product breadth, Dresser took aim at Anthropic’s origins as a coding-focused company. That early wedge, she acknowledged, gave Anthropic an opening — but argued it becomes a liability as AI expands beyond developers into every team and workflow. “You do not want to be a single-product company in a platform war,” the memo states.
The competitive notes were framed as a confidence-builder rather than a warning. Dresser’s broader message was that OpenAI’s biggest constraint heading into Q2 is not demand but capacity — and that the company has the compute, the products, and the customer momentum to extend its lead. Multi-year, nine-figure enterprise deals are rising, she wrote, and existing customers are expanding across OpenAI’s full stack.
Whether the revenue accounting argument lands with the market remains to be seen. The gross-versus-net distinction is a real and documented difference in how the two companies report, and it will matter enormously when both eventually file for IPO. But Anthropic’s enterprise momentum — across customer count, sector leadership, and spending growth — is harder to dismiss with an accounting footnote.
For now, the memo tells us something important: OpenAI is watching Anthropic closely enough to brief employees on its accounting methodology. That is not the posture of a company that thinks the competition isn’t real.