N.C. Gen. Stat. § 153A-203
Any one of several tenants in common or joint tenants (other than copartners) may pay the whole or any part of a special assessment made against property held in common or jointly. Any amount so paid that exceeds his share of the assessment and that was not paid through agreement with or on behalf of the other joint owners is a lien in his favor upon the shares of the other joint owners. This lien may be enforced in a proceeding for actual partition, a proceeding for partition and sale, or by any other appropriate judicial proceeding. This lien is not effective against an innocent purchaser for value until notice of the lien is filed in the office of the clerk of superior court in the county in which the land lies and indexed and docketed in the same manner as other liens required by law to be filed in that clerk's office.
N.C. Gen. Stat. § 153A-203