A file acquisition unit (23a) acquires a collection information file in which collection information defining the carry-out order and collection positions of individual parts nested on a sheet is described. An information reading unit (23b) reads the collection information for each sheet from the collection information file according to a sheet processing order. A group creation unit (23c) virtually performs processing for collecting the parts according to the carry-out order and the collection positions, thereby generating a pile of stacked parts for each collection position. A list creation unit (23d) extracts, for each pile as specified parts, parts stacked at a preset specified position and creates a part list (90). A flag setting unit (23e) sets, for each sheet on the basis of the part list (90), a label flag that defines whether or not to apply a label to each part nested on the sheet.