But have too few redundant copies and you lost access to it forever. Or travel to various countries opening bank vault accounts is sure to put you on CIA/NSA/othersuchagencies' radar. $500M is interesting enough for them to poke around I bet.

Or of you loose access to a country for some other reason you're screwed as well. Also, if you're otherwise not well of spending 10+ thousand to land the secrets in several countries is not an option either