Anthropic Overtakes OpenAI in Business and Heads for an IPO

In April 2026, for the first time, Anthropic overtook OpenAI where it matters most for software vendors, in business adoption. The Ramp AI Index tracks the actual spending of more than 50,000 US companies. It found that 34.4% of them paid for Claude, against 32.3% for OpenAI. A month later, the gap had widened further.

The underdog got past the maker of ChatGPT just as Anthropic prepares one of the largest stock market listings ever seen. The percentages hide a nuance worth knowing, though. If you work with AI, in France or anywhere else, this reversal also changes how you should pick your tools.

01Key points

• In April 2026, Anthropic overtook OpenAI in business adoption according to the Ramp AI Index, with 34.4% of companies paying for it against 32.3%.
• In one year, Anthropic quadrupled its share, from 7.94% in April 2025 to more than 34% in April 2026, while OpenAI gained less than one point.
• Paying for Claude does not mean using it heavily. According to the research firm IDC, about 19% of companies use it intensively, a measure on which Google and OpenAI keep the lead.
• Anthropic filed for an IPO on June 1, 2026, aiming for a listing around October, with annualized revenue close to $47 billion.
• The number one spot can change in a few months. Several API keys and a multi-model tool let you follow the best engine without rewriting everything.

02What the Ramp AI Index shows

The Ramp AI Index measures actual payments, not survey answers. It tracks the corporate card spending of more than 50,000 US companies, which makes it a reliable gauge of what businesses really buy. Its April reading, published on May 13, 2026, marked the moment Anthropic overtook OpenAI, with 34.4% of companies paying for a Claude subscription against 32.3% for the maker of ChatGPT. The June update confirmed the trend, with Anthropic in the lead at around 41% of companies.

The trajectory tells the real story. Claude was used by 0.03% of companies in June 2023 and by 7.94% in April 2025. In twelve months its share quadrupled, while OpenAI's gained only a fraction of a point. The rivalry was decided by the pace of adoption, with no single splashy moment that might quickly fade.

03Why Claude took the lead in business

The shift comes first from one specific use, code and agents. Technical teams chose Claude in large numbers to write, review and fix programs, then to run automated tasks from start to finish. That base of professional use drove adoption far more than the consumer market did. On the cost side, this choice ties into the debate around token-based billing for developers in coding tools.

The other driver is trust. Anthropic built its image on safety and predictability, an argument that reassures IT departments when it is time to sign. That reputation has a downside, though, as the Fable 5 model showed. Its very cautious messaging ended up drawing unwanted attention.

04The nuance behind the figures

An adoption rate says nothing about how intensively a tool is used. More companies pay for Claude, but according to IDC only about 19% use it heavily every day. On that measure of heavy use, Google and OpenAI keep a clear lead. Counting subscriptions and counting actual hours of work give two different rankings, so read both before drawing conclusions.

The same caution applies to the commercial rivalry. OpenAI was still ahead on revenue in the first quarter of 2026. The marketing battle is also fierce, as the AI price war started by Google in consumer AI shows. Anthropic's lead is real, but it covers adoption only and leaves the other indicators open.

05Heading for a record IPO

This commercial success fuels an unusually large financial ambition. Anthropic confirmed that it confidentially filed for an IPO on June 1, 2026. The filing came a few days after a giant funding round that valued the company at nearly $1 trillion. Its annualized revenue passed $47 billion in the spring, after growing fivefold in five months. The listing is expected around October 2026.

The timing is no accident. OpenAI has started the same process, with a listing targeted for the fall. SpaceX's successful IPO on June 13 revived the market's appetite for very large tech deals. So Anthropic is moving fast, carried by demand that far exceeds its current computing capacity.

06What this reversal changes for you

The first lesson is about method, because the top AI provider can change within a few months. Yesterday it was OpenAI and today it is Anthropic. Tomorrow it may be Google or another name. Building all your work on a single provider means betting that its lead will last, while this ranking moves faster than a financial quarter.

The fix comes down to two simple steps. Start by getting your own API keys from several providers, so you depend on none of them. Then use a tool that can switch from one to another in seconds, which is exactly the multi-model approach behind OpenTahr. You follow the best engine of the moment, Claude today, without rewriting your methods the day the top spot changes.

07Frequently asked questions

Has Anthropic really overtaken OpenAI?

Yes, in business adoption. According to the April 2026 Ramp AI Index, published in mid-May, 34.4% of US companies paid for Claude against 32.3% for OpenAI. The June update confirmed Anthropic's lead. On other measures, such as revenue or heavy use, OpenAI remains fully competitive.

Why do companies choose Claude?

Mostly for software development and automated tasks. Technical teams rely on Claude to write and fix code, then to run agents from start to finish. Anthropic's reputation for safety also reassures IT departments when they sign a contract.

When will Anthropic go public?

The company filed on June 1, 2026 and is aiming for a listing around October. It says the number of shares and the offer price are not set yet. The timing will depend on market conditions, so no final date is guaranteed at this stage.

Should you leave OpenAI for Anthropic?

Not necessarily. The smart move is to keep both within reach, with your own keys, so you can pick the best model for each task. That way you can switch without friction the day the value for money tips the other way.

These facts reflect the Ramp AI Index and the specialist press as of June 14, 2026, with links below. Adoption figures and the IPO timeline may change after publication, so check the latest Ramp reading before you rely on these numbers.

08Sources

1. TechCrunch, "Anthropic now has more business customers than OpenAI, according to Ramp data", May 13, 2026.
2. Axios, "Anthropic overtakes OpenAI in workplace AI adoption", May 13, 2026.
3. Ramp, "AI Index" (monthly adoption data), accessed June 14, 2026.
4. VentureBeat, "Anthropic finally beat OpenAI in business AI adoption", May 2026.
5. Yahoo Finance, "Anthropic files confidential S-1", June 2026.