Further, there was Kuro Tsunekiyo SOMA, who was a son of Kazusa no gon no suke (provisional assistant governor of Kazusa Province) Tsunezumi and a younger brother of Hirotsune KAZUSA, and there is a possibility that the old Soma-mikuriya (Kitasoma [northern Soma]), which was donated by MINAMOTO no Yoshitomo, and Minamisoma (southern Soma), which was added when Tsunetane CHIBA made the donation and included many regions with surnames of branch families of the Chiba clan, were separately dominated, and that Kazusa no gon no suke Tsunezumi's son Kuro Tsunekiyo SOMA administered MINAMOTO no Yoshitomo's regions of influence.
また、上総権介常澄の子で上総広常の弟に相馬九郎常清がおり、源義朝の寄進した旧来の相馬御厨（北相馬）と、千葉常胤が寄進したときに追加され、かつ千葉氏庶流の名字の地の多い南相馬とが、それぞれ分割支配されて、上総権介常澄の子・相馬九郎常清が源義朝支配地を管理していた可能性もある。