Apparent authority

Apparent authority (also called ostensible authority) exists where the principal's words or conduct would lead a reasonable person in the third party's position to believe that the agent was authorized to act, even if the principal and the purported agent had never discussed such a relationship. For example, where one person appoints another person to a position which carries with it agency-like powers, those who know of the appointment are entitled to assume that there is apparent authority to do the things ordinarily entrusted to one occupying such a position. If a principal creates the impression that an agent is authorized but there is no actual authority, third parties are protected so long as they have acted reasonably.

This is sometimes termed "agency by estoppel" or the "doctrine of holding out", where the principal will be estopped from denying the grant of authority if third parties have changed their positions to their detriment in reliance on the representations made.