What do you mean by acting as an applicant?

An agent who accepts the entrustment of a patent applicant to handle patent affairs for him. The applicant refers to the party who brings a lawsuit, and the agent refers to the person who handles matters for the applicant. Agency refers to a person who acts as a legal act on behalf of others, and its legal effect directly belongs to the person who acts as a legal act on behalf of others, called an agent.