I don't think Anthropic or OpenAI offer subscriptions to enterprises - it's a hobbyist/solo-entrepreneur kind of thing. I seem to recall SpaceXAI had some kind of hack going where they were trying to use subs with Anthropic and then got cut off.

Enterprises also need very stringent IP protections that you don't get through the subscriptions. Even the Anthropic-API per token license isn't great - sometimes you need to go to 3rd parties like AWS Bedrock to get guarantees regarding no multi-tenant GPUs.