Admin 0 – Boundary Lines
Land boundaries and 200-mile nautical limits. Limited attributes in terms of type of boundary: disputed, treaty, and median lines.
Not every disputed or undefined boundary listed in the CIA World Factbook database is reflected in the main admin-0 boundaries attributes. Care should be taken with regard to undefined or disputed boundaries when attributing to reflect if the dispute is active or not.
If you are showing maritime boundaries, there is a newer, more accurate version at VLIZ, link below. Our version matches with Natural Earth land boundaries and coastline linework and generic version of the VLIZ detailed attributes (update: NE version removed at the request of VLIZ).
VLIZ Maritime Boundaries Geodatabase, version 3 (2009).
Sea Round Us. A global database on marine fisheries and ecosystems. Fisheries Centre, University British Columbia, Vancouver (Canada).