10 C.F.R. § 95.41
External receipt and dispatch records
Each licensee, certificate holder or other person possessing classified information shall maintain a record that reflects:
(a) The date of the material;
(b) The date of receipt or dispatch;
(c) The classification;
(d) An unclassified description of the material; and
(e) The identity of the sender from which the material was received or recipient to which the material was dispatched. receipt and dispatch records must be retained for 2 years.