Anthropic announced Monday it has acquired Stainless, a startup founded by former Stripe engineer Alex Rattray whose software is widely used by rival AI labs, including OpenAI and Google.

Anthropic didn’t disclose terms of the deal. However, The Information 

 last week that the company was in talks to acquire Stainless, which is backed by Sequoia Capital and Andreessen Horowitz, for more than $300 million.

The acquisition will take a key infrastructure supplier out of the hands of Anthropic’s competitors. The company told TechCrunch it will wind down 

, including its SDK generator. An Anthropic spokesperson said Stainless customers will still own the SDKs they’ve generated to date and have full rights to modify and extend them however they wish.

Sick move!

> Anthropic announced Monday it has acquired Stainless, a startup founded by former Stripe engineer Alex Rattray whose software is widely used by rival AI labs, including OpenAI and Google.
>
> Anthropic didn’t disclose terms of the deal. However, The Information [reported](https://www.theinformation.com/articles/anthropic-talks-buy-developer-tools-startup-used-openai-google) last week that the company was in talks to acquire Stainless, which is backed by Sequoia Capital and Andreessen Horowitz, for more than $300 million.
>
> The acquisition will take a key infrastructure supplier out of the hands of Anthropic’s competitors. The company told TechCrunch it will wind down [all hosted Stainless products](https://www.stainless.com/blog/stainless-is-joining-anthropic/), including its SDK generator. An Anthropic spokesperson said Stainless customers will still own the SDKs they’ve generated to date and have full rights to modify and extend them however they wish.
>
> [**...read more at techcrunch.com**](https://techcrunch.com/2026/05/18/anthropic-has-acquired-the-dev-tools-startup-used-by-openai-google-and-cloudflare/)