Two months after Anthropic pushed its most powerful model, Fable 5, into the enterprise market at roughly $10 per million tokens—about double OpenAI's GPT-5.6 Sol—Ramp's August index delivered a brutal number: across 70,000 US businesses, Fable 5 captured only 11.4% of Anthropic dollar spend and 6% of token spend, with growth flat-lining. By comparison, GPT-5.6 Sol took 23% of OpenAI dollar share and 25% of token share.
The revenue picture stings more. In July, Fable 5 generated only about 75% as much revenue as GPT-5.6 Sol. The pool of customers willing to pay top dollar for the strongest model has visibly narrowed in the past year. Ramp economist Ara Kharazian pointed the finger directly at price and data-retention terms: "GPT-5.6 Sol is really good, increasingly the default for developers. Fable 5, meanwhile, disappointed both in adoption and real-world application given price + 30-day data-retention requirements."
It does not stop there. At the end of July, Anthropic shipped Claude Opus 5 at a lower price. Within two months, Opus 5 overtook its own flagship Fable 5 in enterprise spend. Instead of flocking to the most expensive top-tier model, customers drifted toward the cheaper option. The old default—enterprise buyers reaching first for the strongest model—broke in public.
Accel partner Miles Clements summed it up for the FT: the era when customers reached first for flagship models "was not a sustainable era." "Most people don't need to operate at the frontier." In other words, frontier AI labs are still sinking tens of billions of dollars into ever larger and more complex models, but the enterprise buyer's tolerance for a frontier premium just got capped by Fable 5 at roughly $10 per million tokens. Above that, the purchase evaporates.
That said, Anthropic is not losing. On Ramp's broader adoption measure, Anthropic still leads OpenAI at 43.5% of US tracked businesses versus 39.7% in July, and its annualised revenue run rate hit $65 billion that month, up from $47 billion in May. The issue is not user base but unit-economics structure: the flagship did not carry the load, and growth now rides on mid-tier Opus and the lower-priced models.
The deeper takeaway is that Ramp's data quietly rewrites the frontier-lab business-model playbook. For the past decade the story ran: bigger model, stronger model, linearly rising per-token price. Fable 5 is the first hard counter-signal—when customers can hit 90% of their tasks with a 70%-priced model, the frontier premium stops being free. If OpenAI, xAI and Google DeepMind follow up with their own "cheap flagship" hedge, the Fable 5 pricing strategy will turn into an expensive experiment. "The strongest model" is no longer the endpoint of the business story; the real question becomes "who is willing to pay for it, and how much."