It is possible to allow a private image to be shared with one or more alternate tenants. This is done through image memberships, which are available via the `members` resource of images. (For more details, see :ref:`glanceapi`.) Essentially, a membership is an association between an image and a tenant which has permission to access that image. These membership associations may also have a `can_share` attribute, which, if set to `true`, delegates the authority to share an image to the named tenant.
OpenStack ManualsOpenStack Image Service Admin Manual - Diablo
