Article 1637. Accessory nature of the surety’s obligation

(1) The surety’s obligation arises and becomes due only to the extent that the debtor’s obligation to the creditor arises and becomes due.
(2) The surety’s obligation cannot exceed the debtor’s obligation. This rule does not apply if the debtor’s obligation is reduced or discharged:
a) in an insolvency proceeding;
b) for any other legal reason due to the debtor’s inability to perform because of insolvency; or
c) by virtue of law due to an event affecting the person of the debtor.
(3) Any agreement between the creditor and the debtor to make the performance of the secured obligation due earlier, or to make the obligation more onerous by changing the conditions on which performance is due, or to increase its amount, does not affect the surety’s obligation if the agreement was concluded after the suretyship was assumed.
(4) The provisions of paragraph (3) do not apply to global suretyship.