Every complaint to foreclose the right of redemption filed against an unknown owner as described in § 14-837 of this subtitle shall have attached to it an affidavit by the person making the search that the owner of the property or a part of the property is unknown, although a complete search of the records performed in accordance with generally accepted standards of title examination for at least 40 years immediately before the institution of the suit has been made.
Md. Code, TP § 14-838