According to "Shomon ki" (The Chronicle of Masakado), of all the younger brothers of Masakado, only Masayori had the title of Ason (second highest of the eight hereditary titles), so it seems that Masayori had some kind of official court rank, but the details remain unknown.
『将門記』によると、将門の弟達のなかではこの将頼だけが「朝臣」の称号を持っているため、国衙において何かしらの官位を持っていたと思われるが詳細は不明。