OpenAI didn't win Replit by building a better model. It won Replit by charging less — a lot less. According to The Information, OpenAI offered Replit a discount of more than 30% on a contract worth over $100 million a year, and Replit shifted most of its AI spending from Anthropic to OpenAI. Anthropic had refused to extend Replit's prior discount without a higher spending commitment, and OpenAI walked straight through the opening.

This is the second act of a story that started onstage at TechCrunch Disrupt on October 16, when Replit CEO Amjad Masad said his company was no longer working with Anthropic, citing cost, partnership, and performance — and adding, bluntly, "I think ChatGPT is better now." He walked the claim back within a day, and Replit's docs still list seven Claude models. But the money has now confirmed what the walk-back tried to soften: OpenAI is the default provider for Replit Agent, and Claude is the option you have to go looking for.

Replit isn't the only defection. At Rippling, OpenAI's share of engineers' coding work jumped from 16% in May to 52%, while Anthropic's fell from 57% to 18%, according to CEO Parker Conrad. DataCamp says OpenAI's pricing cut its costs by 80 to 90%. Even a US bank with more than $7 billion in assets got its ChatGPT seats doubled to 500 at no extra charge — under $7 per user against a standard price of $20 or more.

The discounting is sustainable, for now, because OpenAI has lowered its own costs through its more efficient Sol and Luna model lines. Anthropic, meanwhile, saw growth slow from Q2 to Q3, according to an investor memo, and faces the same squeeze from cheaper Chinese models from DeepSeek and Kimi.

That's the part worth watching. For two years the frontier labs competed on capability — bigger models, better benchmarks, longer contexts. Now the deciding factor for the biggest coding customers is a line item. The Information's headline for the story put it plainly: "Anthropic's Margin is OpenAI's Opportunity." With Anthropic preparing to go public, it can't afford to keep buying share like OpenAI. But it also can't afford to keep losing $100 million accounts to a rival willing to.

Replit, OpenAI, and Anthropic have not publicly confirmed the financial terms. What is confirmed is the direction of travel: when two models are close enough, the invoice wins.

— via Daily AI Brief