Encrypted group chat is hard to accomplish.
For enterprises concerned about security – and all should be – recognition will long have dawned that email is one of the least secure technologies under the sun.
Encrypted group chat alternatives face a range of issues however: they need to ensure that messages can only be read by members of a given group. They need to be asynchronous: participants may not be online at the same time.
They need to ensure “forward secrecy”: i.e. that full compromise of a node