Remission of debt by the obligee in favor of one obligor, or a transaction or compromise between the obligee and one obligor, benefits the other solidary obligors in the amount of the portion of that obligor.
Surrender to one solidary obligor of the instrument evidencing the obligation gives rise to a presumption that the remission of debt was intended for the benefit of all the solidary obligors.
La. C.C. § 1803