AMP Is open source, Microsoft/Bing are on board, and Google recently stepped back from AMP governance to encourage more parties involved. No one group will hold more than 1/3 control.
Google AMP is not "open source". You might be able to offer suggestions about it, but it's not like a piece of software that you can fork and develop independently. Google controls the main reading device (Google Chrome). The "open source" line is marketing BS.
When I read "no group will hold more than 1/3 control" it sounds like 3 big players will wink at each other while they pillage the WWW and divide the spoils.