Do I need to keep an icon pack installed after using the icon in Nova Launcher?

* I installed an icon pack * Used on icon from the pack as folder icon in Nova Launcher * All other icons in 20MB pack are useless Do I need to keep the icon pack installed on my phone in order to keep using that icon in Nova Launcher? Or did Nova copy the icon to its data, and I can safely uninstall the pack? The question's scope excludes workarounds, such as extracting individual icons from a pack. It's a good idea but for a different question.