National Palace Museum Regulations for the Acquisition of Cultural Relics Article 18

The duration of the custody shall be no less than five years, and it may be extended upon the agreement of both parties. Unless the said agreement specifies otherwise, the owner shall not withdraw the cultural relics within the period of the custody. Exceptions may be made when the needs for withdrawals arise, and they shall be processed on a case-by-case basis. If extended custody is deemed unnecessary by the Museum, the owner shall be notified to withdraw the cultural relics at the end of the custody.