Earlier quoted context omitted.
> Cloud providers must share contributions To be really strict: AGPL only mandates that contributions be shared with the user. The freedom of users is more important than the freedom of developers. Of course an upstream maintainer can be a user and get the contributions.
They have to be shared to the user under the same license. So any user could publish the changes publicly.
For instance, grsecurity will sell you a security-hardening-patched Linux kernel. You, as the user/customer, have the right to take those GPL patches, and share them publicly. But if you do so, grsecurity will blacklist you as a customer, and you won't be able to get any more patches from them.