lobste.rs does something similar: Invite only. But any member can hand out invites. If there's a trend however that you invite the wrong persons I think you c

lobste.rs does something similar: Invite only. But any member can hand out invites. If there's a trend however that you invite the wrong persons I think you can get banned or punished somehow yourself. Edit, exact rules: """There's no limit on how many invitations a user can send (though that might be prompted by scaling problems in the future). When accounts are banned for spam, sockpuppeting, or other abuse, moderators will look up the invitation tree to consider disabling their inviter's ability to send invitations or, rarely, also banning. """ Also there is a public list tree on the site of who invited who: https://lobste.rs/u https://lobste.rs/u