Patent ID: 8369823

Claim:
A method for legitimately unlocking a subscriber identity module (SIM) card lock using an unlocking server connected to an unstructured supplementary service data (USSD) gateway, the method being for unlocking a SIM card lock set by a telecommunications service provider to a mobile terminal of a subscriber, the method comprising: A) receiving an unlocking request that is transmitted from the mobile terminal and through the USSD gateway, the unlocking request including subscriber data and a USSD code representing activation of the unlocking request; B) requesting the telecommunications service provider to verify, with reference to the subscriber data, whether the subscriber has a right to unlock the SIM card lock; and C) upon receiving verification from the telecommunications service provider that the subscriber has the right to unlock the SIM card lock, transmitting an unlocking program and an unlocking password to the mobile terminal such that the mobile terminal may execute the unlocking program and load the unlocking password for unlocking the SIM card lock.