It has been said that the Ida family was descendants of Tanenori IDA who had been the lord of Sakata Castle of Musha County of Kazusa Province, and Takeo said that he was the 25th descendant of the Gyobu no taifu (Senior Assistant Minister of Justice) (from "Biographical Dictionary of Businessmen").
井田家は上総国武射郡坂田城主井田胤徳の末裔とつたえられ､武雄は刑部大輔より25世の子孫であると称している。『実業家人名事典』より。