A registered shareable can only be added once to a site group. Once a registered shareable has been added to a site group, it is available only to members of the site group.
If a site group does not contain any sites, any shareable can be added to the site group. If the site group does contain sites, the sites in the site group cannot be in any existing site groups that contain this shareable.
Open the Business Control Center.
Select Site Administration.
Select the Site Assets link.
Enter the name of a project and click Continue.
Right-click the site group, and select Edit.
The Site Group panel appears.
Select the shared data that are available to all sites within the site group.
Click Save to save the site group.