Neb. Rev. Stat. § 44-710.15: Neb. Rev. Stat. § 44-710.15

The acknowledgment by an insurer of the receipt of notice given under any policy of sickness and accident insurance, the furnishing of forms for filing proofs of loss, the acceptance of such proofs, or the investigation of any claim thereunder shall not operate as a waiver of any of the rights of the insurer in defense of any claim arising under such policy.