10—(1) Subject to subsection (2), any person may intervene in any proceedings on—
(a)an application for a declaration under section 1; or
(b)an application for a variation order.
(2) A person referred to in subsection (1) who is not—
(a)the spouse or civil partner of; or
(b)a close relative of,
the missing person whose presumed death is the subject of the application in question may only intervene in the proceedings on that application with the leave of the High Court.
(3) Without prejudice to the generality of subsection (1) or (2), a person intervening under this section may—
(a)argue before the Court any question in relation to the application which the Court considers it necessary to have fully argued;
(b)where the person is intervening in proceedings on an application for a declaration under section 1, seek the making by the Court under section 4 of any determination or order not sought by the applicant;
(c)where the person is intervening in proceedings on an application for a variation order, seek the making by the Court of a determination under section 5(4) or an order under section 6(2).
(4) In subsection (2)(b), “close relative”, in relation to a missing person, means—
(a)the parent or child of that person; or
(b)the sibling (whether of the full blood or the half blood) of that person.