N.C. Gen. Stat. § 43-28
Upon the institution of any action or proceeding to enforce such adverse claim, notice thereof shall be served upon the register of deeds, who shall enter upon the registry a memorandum that suit has been brought or proceeding instituted to determine the validity of such adverse claim; and summons or notice shall be served upon the holder or claimant of the registered title or certificate or other person against whom such adverse claim is alleged, as provided by law for the institution of suits or proceedings in the courts of this State.
If no notice of the institution of an action or proceeding to enforce an adverse claim be served upon the register of deeds and upon the holder of the registered title or certificate, or other person, as aforesaid, within seven months from the date of filing the statement of adverse claim, the register of deeds shall cancel upon the registry the adverse claim so filed and make a memorandum setting out that no notice of suit or proceeding to enforce the same had been served upon him within seven months as herein required, and that such adverse claim was therefore canceled; and thereafter no action or proceeding shall be begun or maintained to enforce such adverse claim in any of the courts of this State.
N.C. Gen. Stat. § 43-28