5.18.2a PLMN list and SNPN list handling for network sharing

The AMF prepares lists of PLMN IDs or SNPN IDs suitable as target PLMNs or target SNPNs for use at idle mode cell (re)selection and for use at handover and RRC Connection Release with redirection. The AMF:

• provides the UE with the list of PLMNs or list of SNPNs that the UE shall consider as Equivalent to the serving PLMN or the serving SNPN (see TS 23.122 [17]); and
• provides the NG-RAN with a prioritised list of permitted PLMNs or a prioritized list of permitted SNPNs. When prioritising these PLMNs or SNPNs, the AMF may consider the following information: HPLMN of the UE or the subscribed SNPN of the UE, the serving PLMN or the serving SNPN, a preferred target PLMN (e.g. based on last used EPS PLMN) or a preferred target SNPN, or the policies of the operator(s).

For a UE registered in an SNPN, the AMF shall not provide a list of equivalent PLMNs to the UE and shall not provide a list of permitted PLMNs to NG-RAN.

For a UE registered in a PLMN, the AMF shall not provide a list of equivalent SNPNs to the UE and shall not provide a list of permitted SNPNs to NG-RAN.