Authorizing third party specific user identities

An apparatus of a call session control function (CSCF) of an originating service provider for wireless communication, comprising:

• a memory;
• and
• one or more processors, coupled to the memory, configured to:
• receive, from a session initiation protocol (SIP) user agent (UA) of the originating service provider, a SIP INVITE message with a third party specific user identity and a token;
• transmit the SIP INVITE message to an authentication, authorization, and accounting (AAA) server via a network exposure function (NEF);
• and
• receive, from the AAA server via the NEF, an enterprise name card that indicates the third party specific user identity, wherein the enterprise name card is received based at least in part on a verification of the token.

An apparatus of an authentication, authorization, and accounting (AAA) server, comprising:

• a memory;
• and
• one or more processors, coupled to the memory, configured to:
• authorize a use of a third party specific user identity based at least in part on verifying a token associated with a session initiation protocol (SIP) INVITE message with the third party specific user identity;
• and
• transmit, to a call session control function (CSCF) of an originating service provider via a network exposure function (NEF) of the originating service provider, an enterprise name card that indicates the third party specific user identity based at least in part on authorizing the use of the third party specific user identity.