Group management device and group management method

A group management method, comprising:

• receiving information showing required groups that are groups determined to require supplements of the consumables used in image forming devices that are managed per group and;
• performing a supplement instruction of the consumables for the required groups;
• receiving mounting information showing an image forming device mounted with the consumable supplemented in response to the supplement instruction;
• specifying a mounting group to which the image forming device mounted with the consumable belongs based on group correspondence information obtained by associating the image forming device and the mounting group, and the mounting information, and updates the group correspondence information if the required group and the mounting group are different from each other;
• and
• performing an update so that first identification information given to the mounting group and second identification information given to the required group are the same identification information, wherein the same identification information is identification information different from the first identification information and the second identification information.