There should to be a have the way to block the stolen coins.Unfortunately we don't see or have way to block stolen coins.If the codes of the coin show somewhere in blockchain. There should have a way.A software detect it and blocking it.I think we can use the gas system.Everyone pay for transaction.Gas system in scan what they deliver and reject to deliver.So that become useless.You can't get cash from what you have.What is meaning of stealing?