Adopted adults may register a formal veto with the appropriate adoption agency stating their wish not to be approached by an intermediary agency on behalf of a birth relative who is seeking contact. The veto may be absolute - i.e. that an intermediary may not make an approach under any circumstances - or qualified i.e. that the subject only wishes an approach to be made by specified people or in specified circumstances.
A formal veto is not a lifelong veto but will remain in place until the adopted person chooses to amend or withdraw it.