Implicit registration for multiple identities

A device receives a personal Mobile Directory Number (MDN) associated with an individual subscriber, where the individual subscriber is further associated with one or more subscriber devices. The device receives a corporate MDN assigned to the individual subscriber. The device links the corporate MDN, the personal MDN, and the one or more subscriber devices within an Implicit Registration Set (IRS) at a Home Subscriber Server (HSS) in an Internet Protocol Multimedia Subsystem (IMS) for routing calls to the individual subscriber's corporate MDN or personal MDN at the one or more subscriber devices.