The IMEI database maintains 3 different coloured lists. Each has a specific use that benefits mobile network operators and industry affiliates.
As devices have become more sophisticated and more expensive, they are also more attractive to thieves. Recent years have seen an increased need for the IMEI DB to be used as a tool to combat handset theft by ensuring the identities of stolen devices can be shared across networks around the world. The IMEI DB supports what is known as a “Black List”. The black list includes IMEIs associated with mobile devices that should be denied service on mobile networks because they have been reported as lost, stolen, faulty or otherwise unsuitable for use. This list is stored in the GSMA IMEI DB to help operators and other contributors share their individual black list so that devices denied service (blacklisted) by one network will not work on other networks.
The engagement of governments and law enforcement agencies with the network operator community is a powerful way to deter handset theft. In markets where handset theft is perceived to be a problem, the GSMA strongly encourages use of the IMEI DB as a platform to exchange stolen handset data with law enforcement and other operators. Use of the IMEI DB for blacklist exchange is free of charge to member mobile network operators and made available free of charge to government authorities via GSMA Device Check.
Mobile phone users whose devices have been lost or stolen should note that GSMA does not add device IMEIs to the Black List or otherwise assist with incidents of device theft. Device theft should be reported to the subscribers mobile network operator and to the police. For more advice on how to reduce the chances of your device being stolen, and what to do if your device is stolen, click here.
The White List is composed of all Type Allocation Code (TAC, which compose the first 8 digit of an IMEI number) that are permitted for use on cellular networks. Note that the white list does not contain the individual IMEIs or TAC ranges. The information contained in the White List includes the manufacturer, model, equipment type, radio bands and interfaces of the device model.
This information helps Mobile Network Operators identify devices requesting network access and determine if the device is allowed. It is also helpful for knowing what services to offer to the device subscriber and if the device is due for an “over-the-air” software update.
Besides the Black and White Lists, Mobile Network Operators can exchange device status information using the Grey List. Devices on the Grey List are not barred from service but may present a risk worth exploring investigating. For example, if the device is eventually determined to be faulty or troublesome, the Operator may contact the device owner to advise appropriate action.If the device continues to cause problems for the Operator, it could be Blacklisted and barred from service.