However, in his study on the diaries left by nobles and The Tale of Genji, Masakazu SHIKATA found that Noritaka's father, FUJIWARA no Masanori, who was Dazai no shoni (junior assistant governor of Dazaifu, local government office in Kyushu region) under FUJIWARA no Takaie, was mentioned as a resident of Higo Province, and on this finding, Shikata presented a theory that the family was settled in the vicinity of Kikuchi around 1070, during the generations of Masanori and Noritaka, and since then, this is considered as a theory with high credibility.
が、志方正和は公家が残した日記や源氏物語を研究した結果、藤原隆家の下で大宰少弐であった則隆の父藤原政則が、肥後国住人と記述されていることから、政則と則隆の代1070年ころ菊池周辺に土着したとする説を発表、この説が現在まで有力とされている。