Even limitations legislation will allow stolen Bitcoins to eventually re-enter legal circulation. For example, under New Zealand law, if someone (party A) stol

Even limitations legislation will allow stolen Bitcoins to eventually re-enter legal circulation. For example, under New Zealand law, if someone (party A) stole BitCoins from someone else (party B), kept them for 6 years, and then used them to buy something from someone else (party C), party C would have be the sole legal owner of the Bitcoins, because Party B lost their legal right to the property (i.e. right to use the Bitcoins) by losing possession for more than 6 years. Party A could be charged with theft even after the 6 years, but Party C could not be charged with possession because they did not have possession at any point in the first 6 years. Party C could be compelled to identify Party A if they had evidence about Party A's identity. With Bitcoin, Party C and Party A might be the same people, but using different Bitcoin addresses, and it might be hard to definitively prove that they are not the same, especially if Party C puts forward a credible and difficult to disprove transaction in which they obtained the Bitcoins. Disclaimer: IANAL.