4 Use of the equipment identity register
22.0163GPPInternational Mobile station Equipment Identities (IMEI)Release 17TS
A network operator can make administrative use of the IMEI in the following manner:
Three registers are defined, known as "allowed lists", "tracked lists" and "prohibited lists". The use of such lists is at the operators’ discretion.
The allowed list is composed of all number series of equipment identities that are permitted for use.
The prohibited list contains all equipment identities that belong to equipment that need to be barred.
Besides the prohibited and allowed list, administrations have the possibility to use a tracked list. Equipment on the tracked list are not barred (unless on the prohibited list or not on the allowed list), but are tracked by the network (for evaluation or other purposes).