ActivityPub itself is just a protocol, everybody can reimplement it. Lemmy and Mastodon are AGPL3 and thus copyleft along with “you must release source code for your server”.
Though if Meta does anything, I’d expect it to be written from scratch and MIT licensed. Companies don’t like to get near anything GPL as long as they can avoid it.
i’m not sure if ActivityPub is copyleft or not. meta might be able to build proprietary features on top of it if the license isn’t viral.
If it is copyleft, they will probably try to reimplement it permissively.
ActivityPub itself is just a protocol, everybody can reimplement it. Lemmy and Mastodon are AGPL3 and thus copyleft along with “you must release source code for your server”.
Though if Meta does anything, I’d expect it to be written from scratch and MIT licensed. Companies don’t like to get near anything GPL as long as they can avoid it.