Agency coupled with an interest is when an agent has possession or control of the property of his principal and possesses a legal rights against interference by third parties. It is an agency relationship in which the agent is given an estate or interest in the property that is the subject of the agency. It is distinguished from situations in which an agent merely derives proceeds or profits from transactions. An agency coupled with an interest may also be referred to as a power coupled with an interest or a power given as security.
In an agency coupled with an interest, the agent has some legal right to (an interest in) the property that is covered by the agency arrangement, and his position as agent continues until that interest ends. Generally, the ownership of the principal's property does not pass to the agent, whereas in a full trust agreement, ownership does pass to the trustee.
If the agency is coupled with an interest, the agency usually cannot be revoked by the principal before the expiration of the interest and is not terminated by the death or insanity of either the principal or the agent.