Anthropic's IPO filing reveals where OpenAI could have the upper hand
Fortune Emily Forlini ● Covered by 31 sources
Anthropic’s IPO papers show huge growth, but also a slowdown. That gives OpenAI a chance to look better on speed and consumer reach.
Based on reporting by Fortune, Emily Forlini — read the original for the full story.
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Anthropic’s public S-1 has become the first real comparison point for OpenAI’s future IPO filing, and the contrast may end up flattering OpenAI. Analysts already expect OpenAI to tell a different financial story, especially on revenue growth and on the breadth of its business. The company’s consumer side, in particular, could matter more than it once did.
Anthropic’s numbers are eye-watering. Revenue reached $16.3 billion in the first half of 2026, up 1,300% from a year earlier, just five years after the company was founded in 2021. Before that, it went from $41 million in 2023 to $386 million in 2024, then to $4.6 billion in 2025. Even by AI standards, that is absurdly fast. And Anthropic itself is telling investors not to expect the same pace forever.
The filing says the company does not expect revenue to keep growing at comparable rates, and warns growth could slow sharply as the market matures. There is already evidence of that. Fortune pointed out a line in the S-1 implying Q3 2026 revenue of roughly $16.9 billion, which would mean a 47% quarter-on-quarter increase from Q2 to Q3. That’s still huge, but it is a lot less explosive than the 132% jump between Q4 2025 and Q1 2026, or the 144% rise from Q1 to Q2 2026.
OpenAI, meanwhile, appears to be moving in the opposite direction. Investors expect its filing to show accelerating top-line growth, and the company’s own comments suggest its enterprise business is already larger than its consumer business. But the consumer side may be the hidden weapon. OpenAI says it has 100,000 advertisers on ChatGPT, has rolled out another ad format with multiple images, and is preparing hardware devices with Jony Ive that could push ChatGPT into daily life in a more durable way.
Anthropic sees that weakness plainly. Its filing says rivals with stronger consumer brands, bigger user bases, broader distribution, or deeper customer relationships could use those advantages to compete harder in enterprise. So the real question isn’t whether both companies are growing. They are. It’s whether this turns into a business with healthy margins, or just a very expensive race to the bottom with nicer pitch decks.
My take — AI-written commentary, not fact-checked reporting
OpenAI’s consumer push is the part that matters, because enterprise-only AI is starting to look like a contractor business with better branding. The market keeps pretending revenue growth is the same thing as durable profit, which is adorable in a way only Silicon Valley can manage. If this turns into an arms race of discounts and compute bills, the winners may be the chipmakers and the lawyers.
Read more about this at: Fortune
