He was very familiar with yosoku kojitsu (well-versed in usages or practices of the court or military households (practices)) in the imperial court and brought about the best days for the Murakami-Genji (Minamoto clan), but in 1113 Ninkan who was serving as gojiso (budhist exorcists) for Imperial Prince Sukehito of Emperor Gosanjo was believed to have been planning the assassination of Emperor Toba, and handed over the position of head for Murakami-Genji to his younger brother MINAMOTO no Akifusa.
朝廷での儀式に関する有職故実にくわしく、村上源氏の最盛期を築いたが、1113年（永久(元号)元年）子で後三条天皇の皇子輔仁親王の護持僧をつとめた仁寛が鳥羽天皇の暗殺を企てたとされ、弟の源顕房に村上源氏の主流を譲った。