Constrain or package unplaced components by selecting them from the Model Tree, and then right-click and choose Edit Definition from the shortcut menu. After a component is constrained or packaged, it cannot be reverted to unplaced. Unplaced components can be included or excluded when creating a bill of material and are not accounted for in mass properties calculations. When its parent assembly is retrieved into memory, an unplaced component is also retrieved.

You can perform actions on unplaced components that do not involve any knowledge of either the placement in the assembly or its geometry. For instance, you can associate an unplaced component with a layer, but you cannot create a feature on an unplaced component.