TAC Frequently Asked Questions
How can I obtain official TAC from the GSMA?
In order to obtain legitimate TAC, a manufacturer or brand owner should first register their brand via
the GSMA website. Once registered, login credentials are sent to the manufacturer to allow online
application for TAC. Online TAC applications are usually issued within 48 hours.
What devices require TAC?
Any device containing GSM cellular access functionality from the GSM family of standards, eg
phones, smart phones, modems, dongles, tablets, PCs, must include an IMEI number generated from
a GSMA issued TAC code.
Who is responsible for obtaining TAC?
Brand owners
 branding and marketing devices must register with the GSMA and obtain TAC for each different
device model
 subcontracting the manufacture of devices marketed under their brand must register with the
GSMA and obtain TAC for each different device model
Manufacturers
 manufacturing devices under their own brand must register with the GSMA and obtain TAC for
each different device model
 manufacturing devices for another brand do not need to register for TAC as this is the
responsibility of the brand owner
What are Type Allocation Codes?
A Type Allocation Code (TAC) is an 8 digit number allocated to 3GPP device manufacturers by the
GSMA. Manufacturers use TAC to create a unique identifier for a mobile device known as the
International Mobile station Equipment Identity (IMEI). The IMEI is embedded into the device at the
time of manufacture. It must be implemented in such a way that it cannot be modified post
manufacture. The purpose of the TAC code is to identify the device make and model. As such,
different device models require different TAC.
Why are IMEI required for devices?
The purpose of an IMEI is to identify a mobile device make and model. It enables the network
operator to accurately identify the device before allowing it to access the network and block stolen
devices. Without knowing the device model and capabilities, the network operator cannot ensure
proper interaction between the network and device. The device make and model are identified from
the TAC component of the IMEI. Different device models require different TAC.
Why is the GSMA allocating TAC?
The GSMA is appointed by the mobile industry as the Global Decimal Administrator (GDA) for 3GPP
devices &multi- mode 3GPP/3GPP2 compliant devices. GSMA’s role is to ensure TACs are allocated
in compliance with standards, industry agreed practice and worldwide regulatory requirements. GSMA
ensure that officially allocated TAC lead to globally unique IMEI which accurately identify devices.
What does the GSMA do with the TAC it allocates?
The TAC, IMEI and corresponding device details are recorded in a common global database called
the IMEI database. The recorded TAC details are made available to network operators worldwide,
various law enforcement agencies such as Customs and Police as well as other endorsed industry
participants.
How does TAC information benefit the industry?
Currently, TAC allocation services ensure
 Devices can operate globally on mobile networks
 Efficiency of network operation is maintained
Comment [SG1]: Link to
http://imeidb.gsm.org/imei/login.jsp
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Services can be provided to the devices
Differentiation between genuine and counterfeit devices is possible
Stolen devices can be blocked from the networks
Fraudulent insurance claims can be detected
Laundering of stolen devices can be prevented
Who can issue legitimate TAC?
Only GSMA appointed Reporting Bodies can provide official and globally recognized TAC. When you
register with the GSMA, you will be directed to the appropriate Reporting Body for assistance with
obtaining your TAC. Current GSMA Reporting Bodies are:
 British Approval Board for Telecommunications (BABT)
 Mobile Standards Alliance India (MSAI)
 Telecommunications Terminal Testing & Approval Forum (TAF)
 Cellular Telecommunications & Internet Association (CTIA)
 Telecommunications Industry Association (TIA) - Multi-mode devices only
Can I reuse a TAC from a previous model that is no longer in distribution?
No. Once a device model has been allocated a TAC, it is permanently recorded in the IMEI DB since
it is active in the market. Using a TAC from a previous model will render your device inoperable,
cause confiscation of your devices by authorities and invite legal action from the wireless industry.
Can I create my own TAC?
No. TAC must uniquely identify a device model and can only be allocated from the central GSMA
source. False IMEIs and/or TAC are not permitted by the industry. A false IMEI may render your
device inoperable, cause confiscation of your devices by authorities and/or invite legal action from the
wireless industry.
Can I create my own IMEI?
You must not implement an IMEI without the use of an officially allocated TAC Once you have been
allocated a TAC for your device model, you may generate up to a million IMEI numbers from that TAC
and incorporate them into the devices of only that model. A false IMEI may render your device
inoperable, cause confiscation of your devices by authorities and/or invite legal action from the
wireless industry.
Can I use one TAC for different device models?
No. The purpose of a TAC code is to identify a device model. Therefore the same TAC cannot be
used across different device models.