Kokumen no sho (国免荘)
During the late Heian period, kokushi became influential in the provincial government and assumed the authority to decide shoekimenjo (exemption of miscellaneous taxes) on Arata (also referred to as Areta; rice field of low grade) and the like. Kokushi managed to extend his influence even to shoen that had already been granted Fuyu no ken (the right of tax exemption, Japan) and Funyu no ken (the right to keep the tax agents from entering the property, Japan), which had resulted in Kokumen no sho.
Since kokushi gave such treatment entirely at his discretion, that exemption could be cancelled by a newly assigned kokushi. Therefore, the lords of shoen wanted their lands to be granted a much stronger Kanshofu sho (a shoen enjoying immunity from taxation by virtue of having official documents from both the Council of State and the Ministry of Popular Affairs) or Chokumen sho (imperially exempted manor).