The record discloses that on May 2, 1961, counsel for appellants sent by registered mail to Atty. C. Navi Busto, counsel for appelle, the required number of copies of appellants' brief, addressed at Sison, Pangasinan, which was the last known residence of said counsel appearing of record. The registered matter, however, was returned by the postmaster of Sison to the mailing post-office of Lingayen, Pangasinan, marked "Unclaimed," It also appears that before it was forwarded back to Lingayen, the registered package was forwarded by the Sison post-office to Manila, particularly to 3040 Rizal Avenue, supposed to be the address of attorney Busto in said city.

We now have before us a verified petition subscribed by Atty. Busto in which he states that he had received no service of the brief of appellants and that it was only on August 1, 1961 that a copy thereof came into his hands; that the reason for his failure to receive appellants' brief was that in 1961 he had transferred his residence from Sison, Pangasinan, to Calapan, Mindoro Oriental; that upon discovery that appellants had already filed their brief he immediately filed the petition under consideration praying that he be given a period of twenty days from notice to file appellee's brief.

There is no question that appellee's counsel was negligent in not making of record his new address; but considering that he represents appellee, and that no substantial prejudice may be caused to appellants by allowing the filing of appellee's brief, the petition under consideration is hereby granted, with a warning that a repetition of such negligent act will be dealt with more severely in the future. It is so ordered.

Bengzon, C. J., Padilla, Labrador, Concepcion, Reyes, J. B. L., Paredes, and De Leon, JJ., concur.