15-4-4. Release of co-obligor -- Reservation of rights.
Subject to the provisions of Section, the obligee's release or discharge of one or more of several obligors, or of one or more of joint or of joint and several obligors, does not discharge co-obligors against whom the obligee in writing and as part of the same transaction as the release or discharge expressly reserves his rights; and in the absence of such a reservation of rights shall discharge co-obligors only to the extent provided in Section.