Patent attributes
Distributing first shares of a first secret value, known to a first participant, to second participants. The first shares encrypted using a private key and a public key that is elliptic curve generator point multiplied by the private key. A first threshold number of first shares being required to enable a second participant to determine the first secret value. A second share of a second secret value is received from each of the second participants. The second shares encrypted using a private key and a public key that is an elliptic curve generator point multiplied by the private key. A second threshold number of second shares being required to enable a participant other than the second participant to determine the second secret value. A third share of a third secret value formed from the second shares. A third threshold number of third shares being required to enable the third secret value to be determined.