On September 2, 708, the storage of rice in the husk, which was shozei (rice tax), and putting it in fudoso were encouraged in the official documents of the Daijokan, Grand Council of State; afterwards, rice in the husk was stored in shoso (warehouse placed in the provincial government office compounds); when the warehouse became full, the provincial governor and the local officer examined and sealed it; after the sealing was completed, the warehouse was made fudoso and the rice in the husk kept in the fudoso was made fudokoku.
和銅元年8月10日_(旧暦)の太政官符で、正税である稲穀の貯蔵と不動倉設置が奨励され、国衙・郡衙に設置された正倉に貯蔵され、それが満載となると、国司・郡司による検封作業を経て封印されて不動倉とされると、その中に入った稲穀は不動穀とされた。