Section: 5.3.2 Lists of forbidden tracking areas
Content: The UE shall store a list of "forbidden tracking areas for roaming", as well as a list of "forbidden tracking areas for regional provision of service". These lists shall be erased when the UE is switched off or when the UICC containing the USIM is removed, and periodically (with a period in the range 12 to 24 hours). When the lists are erased, the UE performs cell selection according to 3GPP TS 36.304[ Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) procedures in idle mode ]  [21]. One or more tracking areas is removed from the list of "forbidden tracking areas for roaming" in the UE, as well as the list of "forbidden tracking areas for regional provision of service" if, after a subsequent procedure e.g. attach procedure, tracking area updating procedure and GUTI reallocation procedure, one or more tracking areas in the lists is received from the network. If the UE has only one PDN connection established which is for emergency bearer services, the tracking areas shall not be removed from these lists if one or more tracking areas in the lists are received from the network. In S1 mode, the UE shall update the suitable list whenever an ATTACH REJECT, TRACKING AREA UPDATE REJECT, SERVICE REJECT or DETACH REQUEST message is received with the EMM cause #12 "tracking area not allowed", #13 "roaming not allowed in this tracking area", or #15 "no suitable cells in tracking area" or an ATTACH ACCEPT or a TRACKING AREA UPDATE ACCEPT message is received with the forbidden TAI(s). In S1 mode, if the UE receives the "forbidden tracking areas for roaming" IE or the "forbidden tracking areas for regional provision of service" IE in the ATTACH REJECT, ATTACH ACCEPT, TRACKING AREA UPDATE REJECT, TRACKING AREA UPDATE ACCEPT , SERVICE REJECT or DETACH REQUEST message, the UE shall update the suitable list with the TAI(s) included in the IEs which are belonging to the serving PLMN or equivalent PLMN(s) and ignore the TAI(s) which do not belong to the serving PLMN or equivalent PLMN(s). Each list shall accommodate 40 or more TAIs. When the list is full and a new entry has to be inserted, the oldest entry shall be deleted.