Recent years, comparative studies on the Chikama clan in the West and the Ando clan in the East, both of which were Tokuso's bureaucrats taking charge of the respective peripheral border in the east and in the west of the medieval nation, have developed and it is revealed that both of them had a huge extension of the territory compared with the samurai groups in the center, and their territories were even reaching outside the national territory.
近年、中世国家の東西境界周辺の得宗被官である、西の千竈氏と東の安東氏の比較検討研究が進み、ともに中央部の武士団に比べて所領面積が広大であり、国家の境界外に及んでいる点が指摘されている。