I haven’t read the specification carefully enough yet to determine what they mean by “refresh key” since that’s not really a standard term of art. If this could

I haven’t read the specification carefully enough yet to determine what they mean by “refresh key” since that’s not really a standard term of art. If this could refer to a Diffie-Hellman ephemeral, then said key would be generated without requiring a separate private key corresponding to the epoch key, something that’s also not really a standard term. My concern with patents like this is that, since many of the terms are non-standard and thus defined by the specification, any vagueness in the spec leaves room for future interpretations in an infringement case that may, in fact, lead to de facto Signal implementations being found to infringe. ETA: I’ll read the spec later this weekend and see how they define all these terms.