2017-11-21 UTC
# 
@jaywink @DeadSuperHero Well, it's a must if you want to do reply forwarding to all participants.. AP left it out of the spec but when Mastodon did their implementation they realized the forwarding case is impossible without signatures. Shame it's not in spec.
See https://www.w3.org/TR/activitypub/#inbox-forwarding (twitter.com/_/status/933074905536630784)