olemus
dokumendi turvamäärangu osa või lisamäärang,
mis näitab lubatavat levitusala
=
the part of/addition to the document classification marking
that defines the distribution of the document

ülevaateid
https://www.dni.gov/files/documents/FOIA/Public_CAPCO_Register%20and%20Manual%20v5.1.pdf
(see: subsection 8)

https://www.archives.gov/files/cui/20161206-cui-marking-handbook-v1-1.pdf

https://www.totem.tech/how-to-mark-controlled-unclassified-information-cui/