Unless their account's been compromised, it comes from them (and by "compromised" I mean the old-fashioned way, as FB security is good enough to protect their advertisers and their profits). Now, when you join, there's a setting to allow FB to invite everyone in your address book who's not already on FB , but that appears as an invitation to join, not as a friend request (and most people turn that off). "Friending" someone is separate, even if you joined at their invitation.