Agency established by principal's acts, inaction, silence, failure to repudiate

Art. 1869. Agency may be express, or implied from the acts of the principal, from his silence or lack of action, or his failure to repudiate the agency, knowing that another person is acting on his behalf without authority.

Agency may be oral, unless the law requires a specific form.

The act of the principal which constitutes consent may be in the form of silence, lack of action, or failure to repudiate the agency even if he knows that another person is acting on his behalf without authority.

In short, these are the elements:

[1] Awareness of the principal of the acts of the agent;
[2] Reasonable opportunity to repudiate the agent's acts;
[3] Unawareness of the third party transaction that the agent has no authority; and
[4] Good faith on the part of the third party.