Definition - What does Express Authority mean?
Express authority is when a person who acts on behalf of another party has been granted permission to perform a specific act for the person. For example, a financial advisor may be given express authority by their client, who owns the funds, to move money from one account to another.
Justipedia explains Express Authority
Oftentimes, a principal, or an original source, may use an agent, or someone who acts on behalf of the source, to carry out deeds. In these circumstances, when the principal gives the agent the authority to carry out a specific deed, this is called express authority. If the agent performs the deed without permission from the principal, then this would mean that they have acted without express authority. Doing this could breech the contract between the principal and the agent, and could end their agreement.