A method for managing a subscriber device comprising intercepting a Mobile Switching Center or MSC to an Equipment Identity Register or EIR message for requesting whether the subscriber device has or has not been stolen originating from an MSC relating to a home mobile network and being addressed to an EIR relating to the home mobile network, characterized in that the method further comprises: -, as a home coverage presence detection step, detecting by a first device, based upon the interception by the first device of the MSC to the EIR message, a first status (25; 311) relating to a presence of the subscriber device under a radio coverage of the home mobile network; -, as a foreign coverage presence detection step, detecting by a second device a second status (211; 35) relating to a presence of the subscriber device under a radio coverage of a foreign mobile network that borders the home mobile network, the subscriber device being detected successively under firstly a radio coverage of the home mobile network and under secondly a radio coverage of the foreign mobile network or reversely, -, as a first and second status registering step, registering by the first, the second or a third device the first status and the second status; -, as a home border cell identity retrieval step, sending by the second device to an Home Location Register relating to the home mobile network an identity request for getting an identity relating to a latest known cell, and sending to the second device by the Home Location Register relating to the home mobile network a message, as a response to the identity request, including the latest known cell identity; and -, as a home border cell identity registering step, registering by the first, the second or a third device the latest known cell identity, as the home border cell identity. -, as a home coverage presence detection step, detecting by a first device, based upon the interception by the first device of the MSC to the EIR message, a first status (25; 311) relating to a presence of the subscriber device under a radio coverage of the home mobile network; -, as a foreign coverage presence detection step, detecting by a second device a second status (211; 35) relating to a presence of the subscriber device under a radio coverage of a foreign mobile network that borders the home mobile network, the subscriber device being detected successively under firstly a radio coverage of the home mobile network and under secondly a radio coverage of the foreign mobile network or reversely, -, as a first and second status registering step, registering by the first, the second or a third device the first status and the second status; -, as a home border cell identity retrieval step, sending by the second device to an Home Location Register relating to the home mobile network an identity request for getting an identity relating to a latest known cell, and sending to the second device by the Home Location Register relating to the home mobile network a message, as a response to the identity request, including the latest known cell identity; and -, as a home border cell identity registering step, registering by the first, the second or a third device the latest known cell identity, as the home border cell identity.