Who's "LE"?
My guess: Law Enforcement.
Something about this though:
How can we know they will not follow now our BTC to the exchanges we sent them to , and ask for money seizure, confiscation and so on ?
It is a question more related to the exchanges and their forensics software than law enforcement.
Once, a year ago, Chipmixer had some kind of beta testing going on, which was an opportunity for us to use the mixer. Of course, we got those coins back in the form of private keys.
My point being: Today I tracked down the BTC I received from that key, and I noticed it had since went through a couple of transactions, each with different UTXOs (thereby increasing the transaction depth that needs to be explored to find the original chipmixer UTXO) until finally it went into an outgoing transaction with no change.
I'm pretty sure LE is capable of analyzing the 7 TB of seized data, and notify chain analysis companies about the wallets, which they can then label - and taint.
Of course, chain analysis tools cost money, and while LE will probably get them for free or using their massive budget, exchanges are probably less likely to splash 6 to 7 figures a year on chain analysis services. Especially seeing the spectacular nature some of these exchanges have failed (FTX), they probably used entry-level screening with less depth just to say they were compliant with AML.
Whereas you have a public company such as Coinbase who can probably afford the maximum possible screening easily.
So it really depends on the exchange you use. Definitely avoid Coinbase though (as you normally would). Since there's no way to know the transaction depth they use for each of the addresses they analyze - at different tiers of their offerings - you should be safe using non-US exchanges to cash out those chips, then deposit them with some other exchange. As it has been said elsewhere, there're not interested in going after small fish. Only killer whales.
Which means that they'll probably freeze that Minh guy's exchange accounts - and yours too, if you have the misfortune of using an exchange that over-zealously reports everything to the FBI - but they won't go through pains to identify
you specifically just because you have received a Chipmixer chip. Especially if the exchange doesn't share that kind of data about you.
Other things that might help:
- When paying for services online, pay using the Chipmixer UTXOs first (some wallets like Electrum allow you to select specific UTXOs to spend) to reduce the value of "liability chips" you posess.
- Don't use wallets that send change to receiving addresses, or the same address as others. Mostly mobile wallets do this. You don't want to potentially contaminate the rest of your money.
- Don't ever send chips directly to an exchange.
Anyway, I checked using WalletExplorer again, and it seems like it can neither cluster change addresses from Electrum, nor addresses part of the entire chipmixer operation. So at least this removes the majority of internet sleuths from the equation.