N.C. Gen. Stat. § 160A-235
Any one of several tenants in common, or joint tenants, or copartners shall have the right to pay the whole or any part of any special assessment levied against property held jointly or in common, and all sums by him so paid in excess of his share of the assessment, interests, costs, and amounts required for redemption, shall constitute a lien upon the shares of his cotenants or associates, which he may enforce in proceedings for partition, actual or by sale, or in any other appropriate judicial proceeding. The lien herein provided for shall not be effective against an innocent purchaser for value unless and until notice thereof 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 the clerk's office.
N.C. Gen. Stat. § 160A-235