Inzen (a decree from the retired Emperor) (院宣)

"Inzen" is a document which an Inshi (official of the In no cho, or Retired Emperor's Office) issues in a format of hosho (a document informing a decision of the upper ranked personages such as an emperor or shogun) upon direct orders from Daijo Tenno (the Retired Emperor). It is equivalent to an imperial decree issued by the Emperor. It takes a more personal format in comparison to that of an innocho kudashibumi (a letter issued by the In no cho, the Retired Emperor's Office).

According to "Hososhiyo-sho", when the Myobo-ke (judicial officials) interpreted Yororitsuryo Sagi-ritsu (punitive clause regarding fabrication of official documents and government properties under the Yororitsuryo code) earlier, it was described that the fabrication of the Daijo Tenno Zen (a decree by the Retired Emperor) is a crime comparable to the fabrication of the Shosho (an imperial decree), which shows that the concept of inzen could have been in use early in the history. Nonetheless, the first record which mentions the term inzen is "Encho Shichi-nen Daijingu Kanchu", taken from "Dai Nihon Shiryo" (the Historical Materials of Japan) Vol.1, no.6, which was a document that, upon receipt of an imperial decree from Emperor Uda in 927, Ise-jingu Shrine issued as the Emperor Uda's instructions to Shingun (a district designated as a sanctuary which enjoyed certain privileges under an Imperial charter). An inzen was considered as important as, or more important than, an imperial decree issued by the Emperor. As the system of Insei (rule by the Retired Emperor) was enforced in the late Heian period, Chiten no kimi (the Retired Emperor in power) used inzen and innocho kudashibumi to strongly express and achieve his political intentions.

While an innocho kudashibumi, such as Shochoku (imperial edict) and Daijokanpu (official documents issued by Daijokan, Grand Council of State), was a document that expressed the final decision of the government, an inzen was considered a much simpler document from the point of view of its format and efficacy. In other words, while an innocho kudashibumi was issued for important matters of the government, an inzen was used when immediate and flexible actions are required.