Exemplary embodiments relate to techniques for transmitting ephemeral content messages. A sending client may establish an end-to-end encrypted session with possible recipients of the message, using a first decryption key during initial session setup. The client may send an ephemeral content message, including encrypted content and a second key, to the recipients through a server. The server may be unable to retrieve the encrypted content due to a lack of the second key. The server may filter a list of intended recipients, and may forward the ephemeral content message to the recipients on the filtered list. The recipients may retrieve the second key from the message, and use the first and second keys to decrypt the encrypted content. The sending client may change the second key each time the recipient list changes from the perspective of the sending client, as determined at the time the ephemeral content message is transmitted.