Each clan usually had more than one person ranked Shorokuinojo (Senior Sixth Rank, Upper Grade) at any time, and it is considered that a person trying to newly acquire a post of government official submitted a request called moshibumi (general term for a request or petition submitted by a lower authority to a higher) to uji no choja, and uji no choja selected an eligible person.
各氏とも正六位上の者は常に複数いるのが通常であり、新たな官途を得んとする者は、氏長者に対して申文という申請書を提出、氏長者がそのうちから適任者を選考したとされる。