The provision
Art. 1169. Those obliged to deliver or to do something incur in delay from the time the obligee judicially or extrajudicially demands from them the fulfillment of their obligation.
However, the demand by the creditor shall not be necessary in order that delay may exist:
(1) When the obligation or the law expressly so declare; or
(2) When from the nature and the circumstances of the obligation it appears that the designation of the time when the thing is to be delivered or the service is to be rendered was a controlling motive for the establishment of the contract; or
(3) When demand would be useless, as when the obligor has rendered it beyond his power to perform.
In reciprocal obligations, neither party incurs in delay if the other does not comply or is not ready to comply in a proper manner with what is incumbent upon him. From the moment one of the parties fulfills his obligation, delay by the other begins. (1100a)
Key points
A debtor incurs delay (mora) from the time the creditor demands fulfillment, judicially or extrajudicially. Demand is not needed when the law or obligation so declares, when time was a controlling motive, or when demand would be useless. In reciprocal obligations, neither party is in delay if the other is not ready to comply.