Under Federal Rules of Civil Procedure, an action must be prosecuted in the name of the real party in interest.  Admiralty also favors the principle that the real party in interest is a proper party, and the party entitled to relief. For example, where the libel is brought in the name of the carrier against shippers for freight, but the real party in interest is the agent, both under accepted admiralty and civil practice, the libellant should be the agent.  Indeed, a suit in admiralty must be brought by the real party in interest, rather than in the name of one person for the benefit of another.  This principle is flexible, however, and under appropriate circumstances a party may sue for the benefit of another.

For instance, collision suits for damage to the vessel as well as to the cargo are frequently prosecuted only by the owners of the vessel.  In addition, the indorsee of a maritime bill of lading may sue in admiralty for nondelivery of the goods, even though the beneficial interest is in another person.

In admiralty, an agent may sue in his or her own name, for example, where the owners are absent.  The agent may also sue in his or her name in class suits and may do so as well as in the name of his or her principal.  In determining whether a libellant’s proctor was authorized to file the suit which he or she actually filed, the principle is applied that considered steps in litigation taken by a member of the bar of a court are binding on his or her client unless fraud is shown.