Hi,

Make sure to have a backup of all your transactions you've made to and from ALL the exchanges you've traded with.

If you still got every log of transaction and trades, then that proof should suffice to build up a whole history.


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On the other hand, for the sake of preventing abuse by third parties, falsely screwing you over you should use altcoins like ShadowCash, Monero or Dash to cryptographically break the links and traceability of your transactions.

I'm an avid SDC supporter, but in case big transactions I suggest using Monero or Dash because their volume is a lot bigger.