On the other hand, there is an assumption that as the Oga Peninsula of Dewa Province became the Hojo clan's territory after the Tachibana clan lost its control over the peninsula in the mid-Kamakura period, the Ando clan took the position of jitodai (provisional jito) of the territory, and supposes the existence of a branch Ando family, other than the head family, which had an extensive influence over the marine area.
一方で鎌倉中期から橘氏の支配を離れた出羽男鹿半島が北条氏の所領となり、安東氏がその地頭代となったのではないかとする説もあり、宗家とは別の安東一族の海を通じた広がりが推定されている。