If your vendor-risk scorecard ranks OpenAI and Anthropic on the run-rate figures in the press, it is comparing two different accounting methods. OpenAI told investors its annualized revenue was close to $50 billion at the end of September, about $20 billion below the roughly $70 billion that circulated a week earlier, according to the Financial Times as summarized by Investing.com. Most of the gap comes from how partner sales get booked: Anthropic counts the gross value of sales through cloud partners and OpenAI counts only its own share. The two headline numbers you may have been comparing were never on the same basis.
The correction moved markets on October 8. Oracle fell nearly 6%, Nvidia 2.9% and SpaceX 4%, per the AFP report carried by eNCA, and CoreWeave dropped nearly 8%, according to Implicator. For a buyer, the stock moves matter less than the question they expose: what you actually know about the financial footing of the vendor you are about to sign a multi-year commitment with.
Where the Missing $20 Billion Went
The $20 billion is an accounting difference, and it runs through the cloud marketplaces. A gross figure counts the full price a customer paid through a partner as revenue and books the partner's cut as a cost. A net figure counts only the share the vendor keeps.
Bloomberg reported that Anthropic books gross sales through cloud partners such as Amazon, while OpenAI records only its share of certain sales through partners such as Microsoft, and called the comparison "not apples to apples," per AI Weekly's summary of the Bloomberg piece. A Reuters report carried by The Manila Times adds the scale: Anthropic pays cloud partners about 16% of each dollar earned through them, and those sales were half of its revenue last year, according to a Reuters analysis.
The accounts of how the $70 billion figure was produced differ. Bloomberg's sources say OpenAI's investors built it to compare directly with Anthropic. Reuters' source said the gap came mainly from an attempt to compare the two companies, and Reuters also reported that OpenAI had told investors its run rate for August was "approaching $70 billion." Implicator quotes a person familiar with the matter who said the higher number "did not come from OpenAI." Most accounts treat the $70 billion as a gross-style number and the $50 billion as OpenAI's own net figure, though Yahoo Finance says only that the higher estimate "appears" to have used a gross method. OpenAI declined to comment, and Reuters said it could not independently verify the FT report.
Both methods are legal. Implicator says both approaches comply with US GAAP, and quotes accounting professor Francine McKenna, who says the choice turns on which company controls the customer relationship.
Why the Gross-Up Is Lopsided
Converting each company to the other's basis moves OpenAI far more than Anthropic, because the two keep very different shares of a partner sale. Anthropic keeps about 84 cents of each partner dollar. Netting that out is a modest adjustment. As a rough illustration using the Reuters mix from last year (half of revenue through partners, 16% paid away), stripping the partner cut from the $65 billion run rate Anthropic reached by the end of July, per Bloomberg, removes around $5 billion. That figure is arithmetic on reported ratios; neither company has disclosed it. It lands near the "up to $8 billion" gap Semafor estimated in April, as cited by TechTimes.
OpenAI runs the other way. TechTimes reports that OpenAI records roughly 20 cents of each dollar sold through Azure. If a company keeps only a fifth of a channel's sales, grossing that channel up multiplies it several times over, which is how a $50 billion net figure becomes a $70 billion gross one.
The practical consequence: a large share of the OpenAI models your company consumes may be billed by Microsoft, and that spend does not show up as OpenAI revenue at the gross level. If you buy Claude through Bedrock or Vertex, your spend does show up in Anthropic's headline number, partner cut included.
What the Real Numbers Say About OpenAI's Trajectory
On its own net basis, OpenAI is still growing fast, and most of the growth is enterprise. Run-rate revenue grew 77% in the third quarter and enterprise revenue grew 107%, per Implicator, and Yahoo Finance attributes the same 77% and 107% figures to OpenAI's disclosures to investors. Bloomberg reported on October 9 that OpenAI expects annualized revenue to reach $70 billion or more by year-end, driven by enterprise business, per PYMNTS. Implicator calculates that hitting that target requires roughly 40% growth in about one quarter.
For scale, CFO Sarah Friar said annualized revenue passed $20 billion in 2025, up from about $6 billion in 2024, as compute capacity grew from 0.6 to 1.9 gigawatts, per Reuters via Yahoo Finance. Recognized revenue is smaller than run rate. Bloomberg puts OpenAI's projected full-year 2026 revenue at about $35 billion, per AI Weekly, and Implicator reports 2025 revenue of $13.07 billion with a net loss of $38.5 billion.
Run rate itself deserves a discount. It is often calculated by multiplying one month's revenue by 12, analysts told Reuters. Reuters also reports quarterly revenue for Q2 2026 of $6.7 billion for OpenAI against $11.5 billion for Anthropic, the first quarter Anthropic came out ahead. Read that comparison with the same caution: Anthropic's number includes the gross partner sales.
How the IPO Delay Changes Your Contract Risk
OpenAI is now a private company raising capital at a higher valuation while its main competitor heads to the public market first. OpenAI confidentially filed for an IPO in June, and Sam Altman told Fortune on September 11 that "right now would be an ill-advised moment to go public," per PYMNTS. Implicator reports the listing has moved to 2027 at the earliest. Meanwhile OpenAI is in talks to raise $30 billion or more at a $1.4 trillion pre-money valuation, after raising $122 billion at $852 billion in March. Anthropic is expected to list next month, per eNCA.
The strongest counter-argument deserves weight: nothing here suggests either company is close to failing to serve a customer. OpenAI's net run rate more than doubled this year, and a $1.4 trillion round is not a distress signal. The risk to a buyer is narrower and slower. It runs through pricing, packaging and the infrastructure promises behind them.
Those promises are large. Oracle holds a reported $300 billion, five-year cloud agreement with OpenAI, per TechTimes, and Yahoo Finance reports that commitment is about 45% of Oracle's remaining performance obligations. A vendor carrying compute commitments of that size against $35 billion of projected annual revenue has a reason to push customers toward larger prepaid commitments, higher tiers and premium-priced features. You have seen the pattern already in OpenAI's three-year compute commit and in the Q1 burn-rate disclosures.
What to Do Before You Sign or Renew
Put every AI vendor on one revenue basis, then stop using revenue as a proxy for whether the vendor will keep its promises to you. The terms in your contract do that job better.
This Week:
- Find the revenue figures in your current vendor-risk scorecard for ChatGPT Enterprise, Claude and any model you buy through a cloud marketplace. Label each one gross or net and note its date. If your team cannot say which, the score is not usable.
- Pull your own spend by channel: direct from OpenAI, via Azure, direct from Anthropic, via Bedrock or Vertex. That split tells you which balance sheet you actually depend on, and it differs from the headline vendor.
This Month:
- Ask your account teams for recognized revenue or audited figures under NDA, not run rate. If a vendor will only give you annualized numbers, record that in the risk file.
- Re-read the committed-spend terms on any multi-year deal: what happens to unused commitments, whether prices are locked through the term, and what notice you get on model deprecation. The AI vendor exit-clause benchmarks give you the market range to negotiate against.
Before Renewal:
- Add a change-of-control and IPO clause to any OpenAI or Anthropic agreement longer than 12 months: price protection and termination rights if ownership, listing status or the service entity changes. Anthropic's listing is expected first, so start with that renewal.
- Keep a tested second model behind your highest-volume workloads, so you can answer a price change at either vendor by shifting traffic within days.
The Bottom Line
This is the second time this year the OpenAI and Anthropic revenue race has turned out to be partly an accounting question; the April accounting dispute covered the same gross and net split. Expect a third round once Anthropic lists and its revenue recognition appears in public filings. Until then, the most reliable OpenAI figure is the one it gives investors itself, near $50 billion net, with enterprise revenue growing 107% in the quarter.
Before your next renewal, write the basis and the date next to every vendor revenue number in your file.
Continue Reading
- OpenAI vs Anthropic: The $30 Billion Accounting War Behind Enterprise AI
- OpenAI Burns 65% of Revenue: $3.7B Loss in Q1 Alone
- 2 AI Labs Hit $1 Trillion. Your Vendor Strategy Isn't Ready.
- OpenAI Files for IPO: What Changes for Enterprise Buyers
- AI Vendor Exit Clauses: Standard Terms Give 0 to 90 Days to Get Out
- OpenAI's 3-Year Compute Commit: Discount or Trap?
