N.M. Code R. § 13.2.7.12
C. The reinsurance agreement shall provide that:
(1) the agreement shall constitute the entire agreement between the parties with respect to the business being reinsured thereunder and that there are no understandings between the parties other than as expressed in the agreement; and
(2) any change or modification to the agreement shall be null and void unless made by amendment to the agreement and signed by both parties.
[1/1/94; Recompiled 11/30/01]