Say there is a secret encryption key that a third party has to handle. The third party is supposed to destroy the secret key when they are done, and tell everyone else it was destroyed and therefor safe to use. However, if the third party makes a secret copy, then they can covertly sell it for large amounts of money.
Let’s say I want to get a large corporation to be that third party. It is possible for the corporation to make sure no employee can steal the key for themselves without conspiring with many other employees. How could the company show that it instructed the employees to destroy the key? I understand that no legal mechanism can totally prove that no one is lying, but I want to be close.
Sorry if this isn’t actually a legal question.