Think of it like crypto on paper, if you bear it you own it. A bond is just a financial instrument wherein you give a company or government money and after a certain amount of time they pay you back with interest. Think, war bonds during WWII, they won’t make you rich but they are going to pay better than a savings account.
A bearer bond records no transaction of who owns the bond, bearer literally means ‘whoever has it’. If you rob me and take my bearer bonds and then cash them out, the bank (or whoever) isn’t going to stop you. They [the robber] bear the bonds, therefore they [the bonds] are there’s [the robber] as far as anyone is concerned.
The obvious issue with bearer bonds is the same issue with crypto, it is used for illegal things. Tax evasion and the like. Hans Gruber was smart in this regard. You don’t steal cash or gold or whatever, you steal bearer bonds.
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