A2:     According to Article 179 of the Civil Code, “A person who acquires interests without any legal ground and prejudice to the other shall be bound to return it.” The undue enrichment from illegal occupants of national non-public use land should be claimed from the owner of the above-ground objects. Therefore, the compensation for use of the occupied non-public-use national property will be claimed based on the actual length of ownership of above-ground objects acquired for less than five years, and the rest of the compensation for use will be claimed from the original owner of above-ground objects for a length within five years.