OpenAI Gains on Anthropic in U.S. Business Market Share, New Ramp Data Shows

Until both OpenAI and Anthropic get close enough to their planned IPOs to release their financials, we have to look to other sources for signs of how well their businesses are doing. One of those sources, Ramp, the corporate credit card and expense management company, has just released some surprising new data: OpenAI has started gaining on Anthropic with U.S. businesses.

OpenAI, which was once the runaway leader with both businesses and consumers, lost the lead among Ramp’s paying business users back in May. That’s when Anthropic hit 41% market share to OpenAI’s 39%. The ChatGPT maker has never regained that lead. As of July, Anthropic has nearly 44% to OpenAI’s nearly 40%.

The data covers more than 70,000 American businesses that spend billions via Ramp’s bill pay and corporate card products. Ramp’s customers are spread across industries but, as a popular Silicon Valley corporate credit card, they do skew toward the tech industry.

A closer look at the most recent data, according to Ramp economist Ara Kharazian, shows that OpenAI is currently growing faster among this segment in Q3 to date than Anthropic. Mind you, there’s still a month left in the quarter and that’s like 30 AI years, so the trend could easily shift again before it’s over. Ramp also declined to provide actual dollars spent, sharing only percentages.

To borrow ChatGPT’s own hedging style for a moment: This isn’t a measure of the total market. It excludes large enterprises that use spend-management tools from providers like American Express, rather than Ramp. But it’s enough data to show market indications. And what it shows is that Anthropic hasn’t won permanently. Businesses are willing to flop back and forth as each lab releases new models, volatility that should give both companies’ investors pause about how “sticky” enterprise AI spending really is.

“GPT-5.6 Sol is really good, increasingly the choice for developers,” Kharazian posted on X about OpenAI’s new growth. “Fable 5, meanwhile, disappointed both in adoption and real-world application given price + data retention requirements imposed by regulators,” he continued.

That may be an over simplification. Fable — Anthropic’s higher-end model tier — is expensive but it’s also built for a more targeted set of use cases than a general chatbot. Still, Anthropic did cause some outrage when it warned Fable users that it must retain their data for 30 days.

Ramp’s data also suggests that both companies should be growing business revenue, even as they duke it out for market share, because the market overall is expanding. The percentage of companies that pay for AI among these Ramp customers has been steadily climbing. It topped 50% in March. It reached nearly 56% by July.