The opinion
Petitioners raising a challenge under Election Law § 16-102 must complete service on all necessary parties (see Matter of McDonough v Scannapieco, 65 AD3d 647, 648 [2009]). Failure to serve a party mentioned in an order to show cause requires dismissal, even as to those parties who were properly served, if the party not served is a necessary party to the proceeding (see Matter of Wohl v Miller, 63 NY2d 687, 688 [1984]).
Here, as the candidates whose names appeared on the challenged designating petition, the appellants were necessary parties (see Swirsky v Smallwood, 148 AD2d 523 [1989]), and the petitioners’ failure to properly serve the appellants warranted *669 dismissal of the proceeding as jurisdictionally defective (see Matter of DiRoberto v Napoli, 247 AD2d 646 [1998]). Dillon, J.E, Florio, Lott and Cohen, JJ., concur.