N.D. Cent. Code § 26.1-36-27
If an employee, or an eligible dependent of the employee, transfers from coverage provided by a nonprofit health service corporation or an insurance company to coverage offered by a health maintenance organization or transfers from coverage offered by a health maintenance organization to coverage offered by a nonprofit health service corporation or an insurance company and is an inpatient of a hospital or alcoholism treatment center on the day the coverage becomes effective, then the benefits for confinement on an inpatient basis of a hospital or alcoholism treatment center must be provided by the nonprofit health service corporation, insurance company, or health maintenance organization providing coverage on the date the employee or the eligible dependent of the employee was confined as an inpatient of a hospital or alcoholism treatment center so long as coverage is uninterrupted, medically necessary, and directly related to the inpatient's stay.
N.D.C.C. § 26.1-36-27