The appellant taxpayers on September 2, 1965, filed with the Appellate Tax Board a claim of *101appeal to this court under Gr. L. c. 58A, § 13, from a decision of the board denying an exemption under Gr. L. c. 59, § 5, Third, from the real estate tax assessed in the year 1962 on land in Chatham. Pursuant to an extension granted by the board the time for entry of the appeal in this court expired on November 1, 1965. The statute provides that within twenty days after the filing of the claim or such further time as the board may allow, “the appealing party [1]1 shall enter the appeal in said court . . . and [2] shall file with the clerk of said court a copy of the record before the board, [3] shall serve by registered mail upon the adverse party a copy of the claim of appeal and a notice that he has entered said appeal and [4] shall file an affidavit of such service with said clerk. . . . For want of prosecution of an appeal in accordance with the provisions of this section . . . a justice . . . may dismiss the appeal.”
The appellants on October 29, 1965, complied with the first three specified steps. The board of assessors on November 3,1965, moved to dismiss the appeal because of the omission of step 4. The affidavit of service was filed on November 8,1965. A single justice reserved and reported the motion.
We hold that the requirement of the filing of an affidavit of service within twenty days was not jurisdictional. Cohen v. Board of Registration in Pharmacy, 347 Mass. 96. Halko v. Board of Appeals of Billerica, 349 Mass. 465, 467-468. Opie v. Board of Appeals of Groton, 349 Mass. 730, 732-734. W. H. Lailer & Co. Inc. v. C. E. Jackson Co. 75 F. Supp. 827, 828 (D. Mass.). In New England Trust Co. v. Assessors of Boston, 308 Mass. 543, relied on by the assessors, the claim of appeal omitted required assignments of error. In Boston Five Cents Sav. Bank v. Assessors of Boston, 317 Mass. 694, the claim of appeal was not seasonably filed with the Appellate Tax Board. No prejudice or other basis for discretionary dismissal is shown.
The motion is to be denied.
So ordered.
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