Select the Rubrics tool from the Tool Menu of your site.
Select the Revoke sharing icon [Revoke sharing] for the rubric you would like to stop sharing.
Note: You may only revoke sharing for rubrics that have been shared from within the current site. If the rubric had another site of origin, you must go to that site to revoke sharing.
The rubric is no longer shared and has been removed from the Shared Rubrics list.
Note: Revoking a shared rubric has no effect on copies of that shared rubric being used within individual sites.