It is not until around the time that MINAMOTO no Yoritomo became Seii Taishogun (literally, "great general who subdues the barbarians") and established the Kamakura bakufu (Japanese feudal government headed by a shogun) that the family estate is recognized to have been passed down from MINAMOTO no Yoshitada to MINAMOTO no Tameyoshi, then to MINAMOTO no Yoshitomo and then MINAMOTO no Yoritomo; it is uncertain that Tameyoshi was actually the head of the family when he was alive.
源義忠の死後、家督継承が源為義、源義朝、源頼朝と継承されたとするのは、源頼朝が征夷大将軍となり鎌倉幕府を開く前後あたりからのことであり、為義在世中は棟梁として存在していたかは定かではない。