In recent years, however, people find more convincing the story that his base was Shinozuka-jo Castle (present-day in Sakura City), and it is believed that Noritane set this castle as his strategic point and fought against Yoritane.
しかし近年では篠塚城（現在の佐倉市）が根拠地であるとする説が有力であり、なお同城を拠点して自胤と争ったと推定されている。