Blacklisting coins won't work unless all the miners refuse to consider transactions containing them forever. Bitcoin has sender based transactions. All I (the

Blacklisting coins won't work unless all the miners refuse to consider transactions containing them forever. Bitcoin has sender based transactions. All I (the possessor of black market coins) needs to do is to send a small number of coins to a large number of addresses (exchange hot wallets, exchange cold wallets, random people's addresses) and now the taint is spread so wide that in order to enforce the blacklist you need a positive declaration from each of the destination addresses that they are not the thief.