In Reporting and Analytics, click Admin, click Warehouse, click Miscellaneous, and then click Master Groups.
Select a Master Group, and then click Assign Store Master.
Click Add, and then select a Location from the drop-down list.
Select the item types or groups to designate the Master Items. You cannot designate an item type or group as a Master Item if it has been set for another Master Store in the same Master Group.
You can select Assign as location if you deactivate the location as a Master Store.