Patent attributes
Multi-party messaging is disclosed. An encapsulation is received from a first client. The received encapsulation encapsulates an encrypted message encrypted using a symmetric key, and a plurality of keys. Each key in the plurality of keys comprises the symmetric key as encrypted with a respective public key of a respective recipient. An account associated with each of the respective recipients is determined. For each of the respective recipients, a flag is set that is indicative of the arrival of the encapsulation. For each of the respective recipients, which recipients have download the encapsulation is tracked. The encapsulation is deleted.