It doesn&#x27;t matter if they catch Y, as long as he didn&#x27;t keep logs. Nobody, not even Y, knows who Z is, so Z can safely use his coins.<p>&gt;For these reasons, I cannot figure out why they don&#x27;t know who stole the MtGox bitcoins.<p>When you don&#x27;t understand something, something might be wrong with your model. (<a href="http:&#x2F;&#x2F;lesswrong.com&#x2F;lw&#x2F;if&#x2F;your_strength_as_a_rationalist&#x2F;" rel="nofollow">http:&#x2F;&#x2F;lesswrong.com&#x2F;lw&#x2F;if&#x2F;your_strength_as_a_rationalist&#x2F;</a> comes to mind).<p>The exact addresses of the Gox stolen coins aren&#x27;t known AFAIK. Even if they were, to cash out you only need to get someone to accept them without verifying ID. I can send coins to an exchange, and have them send me other coins in a different cryptocurrency, and send those to another exchange, then convert back to btc. If the intermediate currency is something like Monero, then the chain analysis must stop there.<p>I&#x27;m not saying most mixing happens through alts, but it is a fairly foolproof method for anonymity, at the cost of not supporting volume and high fees.<p>Also, you can sell to people for cash, so any investigation hits a dead end. There are probably dozens more ways to cash out anonymously.