RSA 415:18-m Retroactive Denials Prohibited; Exceptions.

I. In this section, "retroactive denial of a previously paid claim" means any attempt by an insurer to retroactively collect payments already made to a health care provider with respect to a claim by requiring repayment of such payments, reducing other payments currently owed to the provider, withholding or setting off against future payments, reducing or affecting the future claim payments to the provider in any other manner.
II. No insurer shall impose on any health care provider any retroactive denial of a previously paid claim or any part thereof unless:
(a) The insurer has provided the reason for the retroactive denial in writing to the health care provider; and
(b) The time which has elapsed since the date of payment of the challenged claim does not exceed 18