So, I've been using an exchange and they asked me to prove the origin of my bitcoins (apparently it's normal procedure).
I want to know how this should be done exactly if my funds were obtained through signature campaigns and dealing online with other individuals? I've had some the funds I'm selling now stored for years (except when I moved them to Trezor when I first bought it) and I can no longer remember the campaigns nor the people I've traded with.
Sucks. I guess this is becoming commonplace. Which exchange, and did they specify what they want exactly? Transaction IDs, screenshots? I agree with LeGaulois; I would keep it as vague as possible.
Also, should I expect them to perform chain analysis or I must provide every TXID that shows the movement of my funds and also threads of these campaigns and their spreadsheets? I also have no longer access to my original addresses (before moving to Trezor) where I originally received the BTC to.
They don't expect private keys so you probably don't need to worry about accessing those addresses. The main question is, will they accept campaign spreadsheets as "proof?" I'm not sure we've seen this tested before.