Yes, there are. First of all, when a multi is unbanned they may only have one account unbanned, to ensure that they will not be able to violate the rules in the future. So if you and your friend are sharing a connection but the two of you start sharing accounts and are banned for it, only one may be unbanned - the other remains banned permanently. Second, if an illegal multi has one account unbanned and violates the rules a second time, they receive a permanent ban for blowing their second chance. Third, occasionally a multi ban is deemed sufficiently severe to warrant a permanent ban, but that is rare.. a permanent ban is more common if another rule is broken in addition, such as exploitation of a feature, hacking, or other rules violations. Multi bans used to be essentially permanent, but that was since replaced with the policy of unbanning one multi with partial asset loss to give players a second chance.