Civil Code, Art. 2144

Whoever voluntarily takes charge of the agency or management of the business or property of another, without any power from the latter, is obliged to continue the same until the termination of the affair and its incidents, or to require the person concerned to substitute him, if the owner is in a position to do so. This juridical relation does not arise in either of these instances: (1) When the property or business is not neglected or abandoned; (2) If in fact the manager has been tacitly authorized by the owner. In the first case, the provisions of articles 1317, 1403, No. 1, and 1404 regarding unauthorized contracts shall govern. In the second case, the rules on agency in Title X of this Book shall be applicable. (1888a)