When the department responsible for land registration, issuing a certificate to the new holder of a right in rem in immovable property, omits to register a mortgage, the right remains in the hands of the new holder, free of the undisclosed mortgage, provided that the issue of the certificate was requested by the interested party as a result of the publication of his title. Without prejudice to any recourse it may have against the State, the creditor benefiting from the omitted registration does not lose the right to avail itself of the rank conferred by this registration as long as the price has not been paid by the purchaser or intervention in the order opened between the other creditors is authorised.