Parts with the same mark are managed internally as a group. If the mark of a part is changed, all the other part marks within a group will change. This tool extracts parts from such a group. The part marks are also deleted and you can give a different number.
Access the command
In the Output tab 
Part Marks panel, click
(Un-group identical parts).
Command line: _AstM5equalpartsReset
Delete the part marks
- In the Output tab Part Marks panel, switch to the single part or assembly.
- Select the element for which you want to define another park mark, independently of the other parts in the group.
- In the Output tab Part Marks panel, click
(Un-group identical parts).
- Click Yes in the warning window.
- The part mark is deleted.