In the Import Settings menu of the Basic menu, use Store Local Copy to toggle between creating a clip with managed media and a clip with unmanaged media.
In both cases, the path to the original media is stored in the clips metadata, allowing the user to toggle between managed and unmanaged media, or even re-importing the media altogether.
You can change how a clip is stored after importing it using the Store tool. See Managing Media Using the Store Tool.
To create clips with managed media:
To create clips with unmanaged media: