Under what circumstance may an agent’s authority not be valid?

An agent’s authority may not be valid when their actions exceed the limitations set by the principal. This situation arises when the agent acts outside the scope of the authority that the principal has granted them. The principal is responsible for the actions of the agent only when those actions are in line with the authority given. If the agent acts beyond those specified limitations, the principal is not bound by the agent’s actions, and third parties dealing with the agent will not have any recourse against the principal for those unauthorized acts.

In the context of agency law, the limitations set by the principal can be explicit or implicit. If, for example, a principal hires an agent to negotiate a contract up to a certain amount, any negotiation beyond that limit would exceed the agent's authority, making those negotiations invalid from the principal’s perspective. This distinction is crucial for determining when an agent is acting on behalf of the principal and when they are acting outside of their granted authority, leading to potential liability issues.