N.C. Gen. Stat. § 143-121.1

The past acts of the Secretary, boards of directors of the institutions and the North Carolina Hospital Board of Control in fixing the rate to be paid by persons admitted are hereby in every respect ratified and validated, and on all claims and causes of action now pending or which hereafter may be made or begun for the payment of the past indebtedness for care, the rates fixed by the party authorized the fix rates at the time the care was provided shall prevail and collections shall be made in accordance with those rates unless the Secretary enters into a contract compromising the account.