In a proceeding pursuant to article 78 of the CPLR to prohibit appellants, who constitute the Public Employment Relations Board, from entertaining an improper practice charge filed by the Half Hollow Hills Teachers Association, Inc. against petitioner, the appeal is from a judgment of the Supreme Court, Suffolk County, entered August 5, 1971, which granted the petition. Appeal dismissed as academic, without costs. In view of Special Term’s vacatur of the judgment appealed from, which had prohibited appellants from entertaining the improper practice charge, the appeal has been rendered moot (Matter of Julius Grossman, Inc. v. Staff, 252 App. Div. 886). Notwithstanding our dismissal, however, we wish to reaffirm our position that a properly filed charge with appellants that petitioner dismissed a teacher because of alleged union activities vests in appellants the power to determine the charge factually (Board of Educ., Cent. School Dist. No. 1, Town of Grand Is. v. Helsby, 37 A D 2d 493; see, also, Matter of City of Albany v. Helsby, 29 N Y 2d 433; Matter of Tischler v. Board of Educ., Monroe Woodbury Cent. School Dist. No. 1, 37 A D 2d 261). Hopkins, Acting P. J., Shapiro, Christ, Brennan and Benjamin, JJ., concur.