Recently a bank had a costly mistake that resulted in their master private key being exposed.
Through this thread, I learned about multi-party key storage with Adi Shamir's secret sharing scheme as the basis, very cool.
In the naive setup, there's still a person/machine that must do the final decryption which knows the full key.
What scheme(s) allows no central decrypter?
A guess I have is two or more 'groups/keys' separately encrypt/decrypt the message so no one group can ever have the keys to the kingdom.
Or is there a way for the final decrypter to decrypt w/o actually knowing the master key such that only one Adi Shamir scheme is necessary?