47 C.F.R. § 80.505 – Points of communication.

(a) Private coast stations and marine utility stations are authorized to communicate:
1. (1) With any mobile station in the maritime mobile service for the exchange of safety communications;
2. (2) With any land station for the purpose of aiding the exchange of safety communications;
3. (3) With ship stations.
(b) Private coast stations of the same licensee may be authorized to communicate on a secondary basis between themselves if:
1. (1) The communications are confined exclusively to those for which authority has been granted the coast station, and concerns ships with which one or both of the coast stations are authorized to communicate; and
2. (2) Other satisfactory point-to-point communication facilities between the coast stations are unavailable; and
3. (3) Coast stations which communicate with each other are not more than 160 km (100 miles) apart; and
4. (4) Harmful interference is not cause to mobile stations.
(c) A private coast station and associated marine utility stations serving and located on a shipyard regularly engaged in construction or repair of commercial transport vessels or Government vessels are authorize to communicate between stations when they are licensed to the same entity and communications are limited to serving the needs of ships on a non-interference basis to other stations in the maritime mobile service. A separate showing is required.