After the mid Heian period, the seiso was placed under the control of the Sugawara clan and the toso was placed under the control of the Oe clan, both of which were to function also as dormitories of the clans as they were (corresponding to the Daigaku besso of the other clans.)
平安時代中期以後、西曹は菅原氏、東曹は大江氏の管理下におかれ、そのままそれぞれの氏族の寄宿舎（他氏の大学別曹に相当する）としても機能した。