Interesting research coming out of Uni of Cambridge. Can bitcoins be tracked? ... used to have issues with tainting the bitcoins but current technology has lead to practical ways to trace stolen bitcoins. im not sure what this means for you and me, like what happens if somehow stolen bitcoins land in my hands... but interesting nonetheless.
Stolen Bitcoin Tracing - Computerphile Yes, the stolen COINS we can check it by transfer wallet address transfer to which account, but because these accounts are anonymous, we cannot to recover our COINS, so when we know the stolen COINS in which account is not of great help for us