I live in the UK as many of you know. I believe it is the same in the EU but fairly recently exchanges are enforcing
The Travel Rule on us.
For those unfamiliar see here -
https://support.kraken.com/articles/updates-to-crypto-transfer-procedures-for-uk-clientsTLDR; When you deposit to the exchange in any size over €1,000 they want to know where the Bitcoin came from. Was it from a cold wallet or another exchange or even from somebody else. You better hope it’s not from somebody else or they’re going to ask you a tonne of questions.
Any way, my personal story was I sold a handful of Bitcoin the first time we went over $90,000. The second sale was for 3 Bitcoin. I got an email saying I needed to confirm where the funds came from. I told them a cold wallet and then I received a support ticket saying Kraken were looking into this and will get back to me before my funds are released.
thats crazy.
for that proof of legit funds or whatever one thing i did back in the day mining in 2011-14 (as that where the bulk of my coins came from - mining) is i screenshotted all pool payouts. and i signed each pool addy i used for pool payouts. time, what equipment (vid cards/fpga/asic). also singed the addy with my name date and some other info that my wife or some lawyer may need.. oh and receipts for the gear.