List X company

From Wikipedia, the free encyclopedia

A List X site is a commercial site (i.e. non-Government) on UK soil that is approved to hold UK government protectively marked information marked as CONFIDENTIAL and above. The term has been used since the 1930s and is equivalent to Facility security clearance (FSC) used in other countries. [1] Companies with this status are those normally involved with Defence research and manufacturing that is vital to national security. The complete list of companies is classified.