A fourth solution is that some were used in flight tests. I did a flight test
that used AIM-4 motors that were shot down the sled tracks at White Sands.
These were motors that were past their shelf life and were condemd from normal
flight. We had a couple of failures but 90% did what we wanted them to do.

3 solutions :
-sold to air forces unable to acquire AMRAAM
-destroy, to comply with desarmement treaty or when out of potential
(missiles are allowed to equipped the aircraft during a number of flight
hours)
-stored in "strategic" warehouse, in case if...