Do chain analysis techniques consider the fee portion of block rewards as tainted funds?
e.g. if known stolen funds are moved in a certain block, the fees the sender pays end up “polluting” the block reward. I want to know how much weight this taint actually gets when it comes to chain analysis. Would the largest exchanges accept these coins as deposits?
If so, then a thief could launder the funds by colluding with a miner. e.g. do a self transfer that pays 10% in fees; don’t broadcast the tx, just pass it to the colluding miner who mines it and later returns a portion of the fees to the thief out of the block reward.
If not, then a thief could taint every block’s reward by simply self transferring a minimal amount with sufficient fees for next block. Then none of the blocks rewards can be deposited in any heavily regulated exchange. I guess miners could censor those txs if the thief’s UTXOs are well known, but it’s still an attack vector I guess.