UID or Unique Identification is a system of establishing universally unique identifiers within the Department of Defense (DoD), United States. Also referred as Item Unique Identification (IUID) in the DoD jargon, this is a combination of standard norms laid down by the DoD for all assets and personal properties including assets in the possession of the contractors. UID helps the Department of Defense to track the items and mange the inventory in its UID registry. As per the DoD mandate, these properties must be marked with a unique serialized identification number in compliant with MIL STD 130. UID or IUID helps the Department of Defense differentiate a separate entity or relationship from other like or unlike entities or relationships. According to the UID specifications of the DoD, all qualifying government items including any fresh requisitioned government PIPC (property in possession of the contractors) or legacy with an objective of placing 100% of property and deliverables in the new UID Registry, should be UID compliant.

The Department of Defense marks the tangible items with a unique identifier (UID) in the form of a number, character string, or sequence of bits assigned to separate entity or its relevant attribute that uniquely distinguish it from other like and unlike entities. As a matter of fact, each and every unique identifier can have only one occurrence within its stipulated scope of use. The IUID is physically marked on tangible assets with the use of a 2D data matrix with ISO 15434 format.

With the UID compliance system in place, the DoD can easily achieve continuous reporting via their Wide Area Workflow System and IUID registry with appropriate UID marking and UID scanning of each and every item at its disposal. Therefore, it has become very important for companies to devise and adopt methods that are UID compliant.