> AMP is a subset of HTML plus some javascript libraries. The subset thing means you had a limited API. That was the point though, the limited API was restricted to the set of things that could be forced to be performant. That is "control" in some sense, but it wasn't control in the common sense of limiting content or ad networks or whatnot. Virtually every ad network had a library for running on AMP.

Javascript libraries that MUST be loaded from one specific Google CDN.

If I load the exact same libraries from my own domain, suddenly it's not "valid" AMP anymore.

It's not a standard if it only works with one specific implementation.

> It's not a standard if it only works with one specific implementation.

IMO, that's sort of what a standard is, but the words is not strictly defined.

I think you are trying to argue that it's not open. The source is on github, and does accept contributions, but effectively Google controls who can commit to it. Depending on your definition of open, that's a valid argument.

You can load those libraries from other locations, but Google search results won't be able to cache it because of the privacy concerns I mentioned in my top level comment. It's not "valid", but the only consequence of the invalidity is no caching, and that consequence is unavoidable given the privacy constraint. It still shows up in search results.

The Google javascript library URL serves with no cookies, is publicly cacheable, and is an identical file to what you can build from source on github.