Bank blocks CoinJoin transactions

[sparroew]

I recently started using Bitcoin and I find it "fascinating" just as I find your work with Wasabi wallet and CoinJoin exceptional.
I have an account at a crypto friendly bank that I very rarely use when I necessarily have to pay for services or goods in FIAT currency. In the bank's clarifications I read: "You must ensure that the origin of the cryptocoins and the wallet from which they are sent are not from a “mixer”, are classified or sanctioned as illicit or there is doubt about it.
If this occurs, we are obliged to inform the relevant authorities and we reserve the right, at our sole discretion, to preventively freeze the cryptocoins".
In practice, if someone sends me BTC and doesn't want to leave traces on the blockchain (even if I know who sends them to me) and if I needed to exchange them for FIAT, my bank wouldn't exchange them for me or, worse, freeze them. So, using the Wasabi CoinJoin my bank would not allow me to change the coins and I ask you how does the bank know that the coins are the product of a coinjoin, is anything readable written on blockchain explorer? Thank you
Kind regards

[Kruwed]

WabiSabi coinjoin transactions have a distinct on chain footprint: Users who send you coins or receive coins from you can tell that you used Wasabi (or other coinjoin supporting wallet like BTCPay Server/Trezor), but they cannot tell where your coins originally came from or went to: All they can see is the coinjoin.

If you want to blend in with others while still retaining your privacy, there is another kind of coinjoin transaction Wasabi can create called a payjoin that has the potential to avoid this footprint, but no exchanges I know of support it, only some merchants using BTCPay Server.

Furthermore, you can open Lightning channels with your coinjoined outputs, so if your exchange supports Lightning, you can deposit with an extra layer of privacy that prevents them from knowing you originally used a coinjoin to create your Lightning channel. You can read more about Lightning's privacy here - https://lightningprivacy.com

[sparroew]

Many thanks Kruwed, I think it is a problem to try to solve because if, like my bank which is crypto friendly, other banks will use the same policy and this extends to exchanges, goodbye to privacy... we already have very little of it in ours lives.

[kristapsk]

If you care about privacy, you should look at P2P Bitcoin trading platforms instead of banks / KYC exchanges, like hodlhodl.com and Bisq Network.