US Patent 11962679 Secure distributed key generation for multiparty homomorphic encryption

Collaborative multiparty homomorphic encryption comprising receiving a linear common public key collaboratively generated by a plurality of parties as a sum of linear public key shares associated with the respective plurality of parties. Each of two ciphertexts may be encrypted with the linear common public key and the two ciphertexts may be combined by a non-linear computation to generate a result ciphertext encrypted by a non-linear public key. The result ciphertext may be re-encrypted with a re-linearization key to swap encryption keys from the non-linear public key to a linear public key. The re-encrypted result ciphertext may be distributed to the plurality of parties to each partially decrypt the re-encrypted result ciphertext by a linear secret key share associated with the party, which in combination fully decrypts the result by a linear common secret key that is a sum of the secret key shares of the respective plurality of parties.