Going over Microsoft's FAQ on their new Sender-ID license, I noticed the following statement:
The original CallerID patent application was filed long before Microsoft made a decision to contribute its CallerID specification to the IETF
The original Caller ID specification was submitted to the IETF sometime around the Spring of 2004, after the MARID WG formed. "Was filed long before" sounds like a pretty long times, however the facts are pointing in a different direction.
Draw your own conclusions.