During the Japanese occupation, the Governor's Office exercised various supervision over commercial activities. For example, traders and manufacturers must obtain permission and register from the Governor's Office before they started their business. The sorts of import and export goods were also came under strict scrutiny. Military scrip was the sole legal tender at that time.

This invoice dated in Showa 18th Year (1943) shows the control on commercial activities during the Japanese occupation.

Records of the details of businessmen and their companies
Invoice dated 1943