Anthropic Lines Up a Listing as OpenAI Stays Private

Anthropic is preparing a U.S. listing after Claude’s business hit a $47 billion run rate, and OpenAI chief executive Sam Altman has taken a 2026 debut off the table.

The two labs spent the first half of 2026 selling the same idea of a dual IPO race. The calendar now has one company getting ready to show its books, and one that is not.

OpenAI Rules Out 2026 as Anthropic Lines Up a Listing

On September 12, 2026, Altman said a public offering this calendar year would be a bad time, and pointed to safety and alignment work he wants to do while OpenAI is still private. A person familiar with Anthropic’s plans said on September 13 that the Claude maker has selected Nasdaq and is still aiming at an October window. Anthropic has not posted its own listing notice.

OpenAI already told the market the timing was loose. On June 8, 2026, the company said it had sent in a confidential S-1 and that a listing easier as a private company might still win out. Altman’s September remarks closed the 2026 door in public.

Estimates circulating around an Anthropic deal have stretched toward $2 trillion, with talk of a raise that could run to $100 billion. Those figures have not come from a prospectus. The last number Anthropic put on itself is the May round.

WHAT WE KNOW

• May round: Anthropic raised $65 billion at a $965 billion post-money value on May 28, 2026.
• Company run rate: Anthropic said that month its run-rate revenue crossed $47 billion.
• OpenAI filing: OpenAI announced a confidential S-1 on June 8, 2026, and Altman later ruled out a 2026 listing.
• Cloud footprint: Claude already runs on AWS, Google Cloud, and Microsoft Azure, with AWS still named as the primary training partner.

WHAT IS UNCONFIRMED

• Exchange and date: Nasdaq and an October window come from a person familiar with the plans, not from Anthropic.
• Deal size: A $2 trillion value and a $100 billion raise remain market talk.
• Anchor check: Talk of Nvidia putting in as much as $10 billion has not been confirmed by either company.
• Profit: Outside models have sketched a first profitable quarter; Anthropic has not published audited quarterly results.

U.S. securities rules still force the next hard step. Before any roadshow, the company has to make a prospectus public, which means the run rate, the cloud contracts, and the gross margin all land in one document.

THE 2026 LISTING CALENDAR

1. February 2026: Anthropic closes Series G and says more than 500 business customers each spend over $1 million a year.
2. April 6, 2026: Run-rate revenue surpasses $30 billion, and the $1 million-customer count exceeds 1,000.
3. May 28, 2026: Series H prices at $965 billion and the company states a $47 billion run rate.
4. June 8, 2026: OpenAI announces a confidential S-1 and leaves timing open.
5. September 12, 2026: Altman says a 2026 listing is off.
6. September 13, 2026: A person familiar with the plans says Anthropic has picked Nasdaq.

That sequence is why the old dual-track story no longer holds. One lab is walking toward public investors. The other just said it will not, at least not in 2026.

A $47 Billion Run Rate Reordered the Race

The listing talk only got loud after Claude’s revenue line moved. On April 6, 2026, Anthropic said run-rate revenue had surpassed $30 billion, up from about $9 billion at the end of 2025. Seven weeks later the company put the May figure at $47 billion.

IDC, in June 2026, put OpenAI’s annualized revenue in a $30 billion to $40 billion band, with about $10 billion to $13 billion from consumer subscriptions and as much as $20 billion from API and platform use. ChatGPT still dwarfs Claude on reach. IDC estimated about 900 million weekly ChatGPT users. Anthropic’s consumer subscriptions, the same research house said, were less than $2 billion.

That mix is why Anthropic flipped the AI revenue race even while OpenAI kept the household name. Counterpoint Research, looking at the first quarter of 2026, gave Anthropic 31.4% of global large-language-model revenue and OpenAI 29%. It also put average monthly revenue per user at $33.3 for Anthropic and $2.2 for OpenAI.

THE TWO LABS ON PAPER

Gil Luria, an equity analyst at D.A. Davidson, said in June that current growth rates for both firms are the fastest they will ever be, which is mostly math, and that some of the largest enterprise customers may start capping token spend. That is the other side of a $47 billion run rate. The same usage that fills the top line is what the cloud invoices meter.

Ten Gigawatts of Cloud Sit Under the Filing

Anthropic’s own May notice listed the capacity it had just signed: up to five gigawatts of new Amazon capacity, five gigawatts of next-generation TPU capacity with Google and Broadcom, and GPU access in SpaceX’s Colossus 1 and Colossus 2. AWS remains the primary cloud and training partner, the company said, and Claude is sold on all three large clouds.

Those are not optional add-ons. In April, CFO Krishna Rao called the Google and Broadcom pact the company’s most significant compute commitment to date, made to keep up with demand that had already pushed the run rate past $30 billion. A November 2025 pledge to put $50 billion into American computing capacity sits under the same stack, with most of the new TPU sites planned for the United States and capacity expected online starting in 2027.

THE CAPACITY ANTHROPIC HAS ALREADY NAMED

• Amazon: Up to five gigawatts of new capacity, and $5 billion of the $15 billion in prior hyperscaler money inside Series H.
• Google and Broadcom: Five gigawatts of next-generation TPU capacity, expected from 2027.
• SpaceX: GPU access in Colossus 1 and Colossus 2.
• Three-cloud sales: AWS Bedrock, Google Cloud Vertex AI, and Microsoft Azure Foundry.
• U.S. build pledge: $50 billion announced in November 2025, expanded by the later TPU deal.

A September tally of contracted and reported deals put the decade-long compute book at $517 billion, up from about $180 billion through 2029 that Anthropic had previously described to investors. In that tally, Amazon and Google together account for about 11 gigawatts and more than $300 billion over roughly ten years, Microsoft is in for at least $30 billion of Azure capacity, and the SpaceX path runs up to about $45 billion. Anthropic has not published that $517 billion figure itself. Public investors will still have to underwrite whatever slice of it is firm when the prospectus lands.

Amazon and Google Get Paid Either Way

The listing does not loosen those leases. It is how a private lab pays for them without another private round the size of Series H. Amazon already sits on both sides of the ledger: it is a backer, it is the primary cloud, and it sells Claude through Bedrock. Google sells TPU capacity and carries Claude on Vertex. Microsoft, OpenAI’s long-time partner, also hosts Claude on Azure and, in the September tally, shows up as a supplier to Anthropic as well.

Series H made that dependence explicit. Micron, Samsung, and SK hynix joined as infrastructure partners, a way to line up memory and logic supply rather than a software story. Altimeter’s Brad Gerstner, Sequoia’s Alfred Lin, and the other lead investors are buying a claim on Claude’s enterprise seats. The hyperscalers are selling the watts those seats consume.

Anthropic has already shown it will pass on a large purchase when the fit is wrong. It walked away from a $6 billion bid earlier in this cycle. The checks it keeps writing are for servers, chips, and long-dated cloud. A public listing is the financing tool that matches that habit.

OpenAI’s cost problem is the same shape with a different landlord. Its consumer reach is the product that made the category. Inference, unlike a training run, repeats on every query, so the Azure bill scales with the 900 million weekly users rather than with a single model drop. Staying private for another year keeps that invoice out of a quarterly 10-Q.

Why Altman Wants Another Year Private

Altman’s stated reason is safety. He told Fortune editor-in-chief Alyson Shontell that OpenAI does not feel pressure to list, that the company will go public when it is ready, and that 2026 is not the year.

We’re not rushing into an IPO. I actually think that, given everything happening with safety, this would be, right now would be an ill-advised moment to go public. And we don’t feel pressure on that. We’ve said for a long time, we’ll do it when we’re ready. I would say not 2026. We’ve got a lot of stuff to do.

Sam Altman, Chief Executive, OpenAI, in a Fortune interview

A public company has to put a P&L next to those words. That document would show how much of ChatGPT’s usage turns into gross profit after inference, how much is still committed to future clusters, and how much of the next model class depends on partners who already have their own models on the same cloud. Safety is the reason Altman gave. The filing is the document that reason postpones.

OpenAI’s June notice had already left room for delay. The S-1 was filed so the company would have the option. Altman used the option. If Anthropic does list first, public markets will print a multiple on an enterprise-weighted Claude business before OpenAI ever has to answer the same questions about a consumer-weighted one.

Coding Seats Now Carry the Revenue Mix

Claude Code is the product that made the enterprise line move. Anthropic has said the coding tool reached $1 billion in annualized revenue within six months of its May 2025 launch and more than $2.5 billion by February 2026. Krishna Rao, the CFO, named Claude Code and Cowork in the Series H note as the tools the company is trying to make more useful for the same customers who are driving demand.

The customer count moved with it. When Anthropic announced Series G in February 2026, more than 500 businesses were each spending over $1 million a year. By April 6 that roster had more than 1,000 business customers at that level, doubling in less than two months. IDC’s picture of Anthropic as an enterprise and developer shop, with consumer subscriptions under $2 billion, matches that roster. OpenAI still has the consumer surface. Anthropic has the expensive seats.

WHERE THE MONEY SHOWS UP

• Anthropic consumer: Less than $2 billion, per IDC in June 2026.
• OpenAI consumer: About $10 billion to $13 billion inside IDC’s $30 billion to $40 billion band.
• Claude Code: $1 billion annualized within six months of launch, more than $2.5 billion by February 2026, per the company.
• Heavy accounts: More than 1,000 customers above $1 million a year as of April 6, 2026.

Dario Amodei has described software engineers as the fastest adopters, and coding as a preview of how the rest of the economy takes up the models. That is a nice story for a roadshow. It is also a concentration risk. If those 1,000 large accounts do what Luria flagged and start rationing tokens, the run rate that justifies a listing is the same run rate that can slow.

The Prospectus Has to Show the Cloud Bills

Rao’s May pitch to investors was demand, research, and putting Claude where work already happens. The next audience is public, and it will price the same speech against the contracts behind it.

This funding will help us serve the historic demand we are experiencing, stay at the research frontier, and bring Claude to more of the places where work happens.

Krishna Rao, Chief Financial Officer, Anthropic, Series H announcement

Lead underwriters named around the deal have included Goldman Sachs, Morgan Stanley, and JPMorgan. That is not a substitute for the income statement. The May round already folded in $15 billion of prior hyperscaler money. A listing would add public equity on top of that stack, which is how a lab with a $47 billion run rate still needs the market: the customers arrived, and the cloud bill arrived with them.

OpenAI will watch that print from the private side of the line. Altman has bought another year. Anthropic is the company that has to show, in a prospectus, how a coding-and-API business pays for five gigawatts at Amazon, five gigawatts of TPUs, and the rest of a decade of compute that a September tally already stretched past $500 billion.

Disclaimer: This article is news reporting and analysis for general information only. It is not investment advice, a solicitation, or a recommendation to buy, sell, or hold any security, including any potential Anthropic or OpenAI shares, related cloud stocks, or pre-IPO interests. Readers who are considering an investment decision should consult a licensed financial adviser or securities attorney who can review their own facts, risk limits, and the actual offering documents if and when those documents exist. Revenue run rates, valuations, listing venues, and compute figures here reflect company statements and third-party estimates available on September 13, 2026, and those figures can change as filings, contracts, and customer usage move.