Rule 13A—(1) At any stage in a claim to which this rule applies, the Court may, on the application of any party or of its own motion, direct that notice of the claim be served on any person who is not a party thereto but who will or may be affected by any judgment given therein.
(2) An application under this rule may be made without notice being served on any other party and shall be supported by a witness statement or affidavit stating the grounds of the application.
(3) Every notice of a claim under this rule shall be in Form No. 52 in the relevant Practice Direction and shall be issued out of the appropriate office, and the copy to be served shall be a sealed copy accompanied by a copy of the claim form and of all other statements of case served in the claim and by a form of acknowledgment of service with such modifications as may be appropriate.
(4) A person may, within 14 days of service on him of a notice under this rule, acknowledge service of the claim form and shall thereupon become a party to the claim, but in default of such acknowledgment and subject to paragraph (5) he shall be bound by any judgment given in the claim as if he was a party thereto.
(5) If at any time after service of such notice on any person the claim form is amended so as substantially to alter the relief claimed, the Court may direct that the judgment shall not bind such person unless a further notice together with a copy of the amended claim form is issued and served upon him under this rule.
(6) This rule applies to any claim relating to—
(a)the estate of a deceased person; or
(b)property subject to a trust.
(7) CPR rule 7.2(2) shall apply in relation to a notice of a claim under this rule as if the notice were a claim form and the person by whom the notice is issued were the claimant.