Minn. Stat. § 62A.60

In cases where the subscriber or insured is liable for costs beyond applicable co-payments or deductibles, no insurer may retroactively deny payment to a person who is covered when the services are provided for health care services that are otherwise covered, if the insurer or its representative failed to provide prior or concurrent review or authorization for the expenses when required to do so under the policy, plan, or certificate. If prior or concurrent review or authorization was provided by the insurer or its representative, and the preexisting condition limitation provision, the general exclusion provision and any other coinsurance, or other policy requirements have been met, the insurer may not deny payment for the authorized service or time period except in cases where fraud or substantive misrepresentation occurred.