Assembly Design > Using Assembly > References and Dependencies > Reference Control > About Reference Backup
  
About Reference Backup
For component placement and when a feature is defined using external references, you can create a geometry backup to support placement or feature regeneration and redefinition when the references are out of context or out of session. The geometry backup appears as a Copied References or Geometry Backup feature sub-node in the Model Tree. (Copied References and Geometry Backups are visible when you display Copied references in the Model Tree.) You can change the update control set for copied references and geometry backups.
Reference backups are automatically created when the appropriate reference controls are turned on. You can also create reference backups manually from the Model Tree for individual components and features, right-click the component or feature and select References > Back Up References. Use Operations > References > Back Up All References to backup all references in the assembly. When the original model is in session, you can update the reference to reflect changes to the original model.
You can remove manually created reference backups in one of the following ways:
To remove reference backups from individual components or features, right-click the component or feature in the Model Tree and select References > Remove Backups.
To remove all reference backups in the assembly, click Operations > References > Remove All Backups
It is recommended to remove backups only when the update control is set to Automatic.