Scholars hold divergent views, including the speculation that Tanemichi and his successors moved and lived in Mutsu Province, that which presumes the family remained in Shimousa but they possessed the land in Mutsu Province to where only members of the family were sent, and that which assumes that the family neither moved to Mutsu province nor owned that land.
学説的には、胤通と以降の国分氏惣領が代々陸奥国に居住したとするもの、領有は認めるが移住は否定し庶子が派遣された程度であろうとするもの、領有も移住も否定するものに分かれる。