R.I. Gen. Laws § 44-9-39

Any person having a right of redemption or any other interest in the land conveyed or purporting to be conveyed under § 44-9-36 or 44-9-38, upon whom service of the notice of sale provided in § 44-9-36 has been made by registered or certified mail, who, prior to the sale, neither redeems the land nor brings proceedings to enjoin the sale, shall, upon the recording of the deed as required by § 44-9-36 or 44-9-38, be forever barred from raising any question concerning the validity of the title conveyed, and a statement contained in the treasurer’s deed that service has been made, naming the persons who were served by registered or certified mail, shall be prima facie evidence of service (Form 12).