Ownership of bitcoin or recipt (in a previous transaction) are easily, provable, what is more, once proof is provided it is irrefutable. All someone need do is

Ownership of bitcoin or recipt (in a previous transaction) are easily, provable, what is more, once proof is provided it is irrefutable. All someone need do is point to a record of a transaction in th blockchain and provide the keys that verify ownership of this address. This guy doesn't know what he's doing.