Top Level Telecommunications often involve information that has to be kept secret. To ensure that, governments have systems to protect sensitive information by classifying it, which is best known from document markings like "Top Secret".
Here we'll explain the classification system of the United States, which is far more complex than most people think, also because it's one of the world's biggest secrecy systems. In 2012 almost 5 million (!) people in the US had a clearance for access to classified information.*
The deeper parts of this classification system are classified, but some new details and codewords have been revealed in documents from the recent Snowden-leaks.
Classification markings
All documents that contain classified information, whether digital or hard copy, have to be marked with the appropriate markings. These are shown in the classification or banner line, which is shown at the top and bottom of every document and usually has three parts, separated by double slashes:
Additionally, all sections of a document should have a portion marking, which is an abbreviation of the full classification line. Below, the abbreviations for these portion markings are shown in brackets.
When a document contains joint or Foreign Government Information (FGI), the necessary markings are shown in a separate part of the classification line. These markings will not be discussed here.
The meaning of abbreviations and codewords can be found in the separate listing of Abbreviations and Acronyms and the listing of Nicknames and Codewords.
Classification levels
The United States government classifies information according to the degree which the unauthorized disclosure would damage national security. Like many other countries, the US has three classifications levels. From the highest to the lowest level these are:
- TOP SECRET (TS)
- SECRET (S)
- CONFIDENTIAL (C)
Government documents that do not have a classification can be marked as:
- UNCLASSIFIED (U)
With 1.4 million people having a Top Secret clearance, it's more than clear that additional measures are needed to protect the more sensitive information. Therefore, that information is put in separated compartments, only accessible for those people who have the 'need-to-know'.
This is called Sensitive Compartmented Information (SCI) for intelligence information, while other highly secret and sensitive information is protected by a Special Access Program (SAP). Both sub-systems will be explained below.
SCI compartments
Sensitive Compartmented Information (SCI) is a system to protect national intelligence information concerning sources and methods, and is divided into control systems and compartments, which are further subdivided in subcontrol systems and subcompartments. These systems and compartments are usually identified by a classified codeword, some of which have been declassified. In total, there may be between 100 and 300 SCI compartments and subcompartments, grouped into about a dozen control systems.
- COMINT or Special Intelligence (SI)
- TALENT KEYHOLE (TK)
- HUMINT Control System (HCS)
- KLONDIKE (KDK)
- RESERVE (RSV)
- BYEMAN (BYE or B, defunct since 2005)
- VERDANT (VER)
- PANGRAM (PM)
- MEDITATE (M)
- SPECTRE (?)
- LOMA (?)
- Special Navy Control Program (SNCP)
- STELLARWIND (STLW)
- an undisclosed codeword has the abbreviation OC
In a classification line this is shown like: TOP SECRET//SI
Multiple control systems are shown like: TOP SECRET//SI/TK
COMINT (SI)This control system is for communications intercepts or Signals Intelligence and contains various sub-control systems and compartments, which are identified by an abbreviation or a codeword. In a classification line they follow COMINT or SI, connected by a hyphen.
Known COMINT sub-control systems are:
- Very Restricted Knowledge (VRK)
- Exceptionally Controlled Information (ECI)
- GAMMA (G)
- DELTA (D, now defunct)
In a classification line this is shown like: TOP SECRET//SI-ECI
Exceptionally Controlled Information (ECI)This sub-control system of SI contains compartments, which are identified by a classified codeword. In the classification line there's a three-letter abbreviation of this codeword.
Recently disclosed codewords for ECI compartments are:
- AMBULANT (AMB), APERIODIC, AUNTIE, PAINTEDEAGLE, PAWLEYS, PENDLETON, PIEDMONT, PICARESQUE (PIQ) and PITCHFORD. There's also an undisclosed codeword which has the abbreviation RGT.
In a classification line this is shown like: TOP SECRET//SI-ECI PIQ
Multiple compartments are shown like: TOP SECRET//SI-ECI PIQ-ECI AMB
GAMMA (G)This sub-control system of SI is for highly sensitive communication intercepts and contains compartments, which are identified by an identifier of four alphanumercial characters. In the past this were four-letter codewords, but it's not clear whether this practice is still used today.
Some former GAMMA compartments were:
- GABE, GANT, GILT, GOAT, GUPY, GYRO and GOUT
In a classification line this is shown like: TOP SECRET//SI-G GUPY
TALENT KEYHOLE (TK)This control system is for products of overhead collection systems, such as satellites and reconnaissance aircraft, and contains compartments, which are identified by a classified codeword.
Some former TK subcompartments were:
- CHESS, RUFF and ZARF
In a classification line this is shown like: TOP SECRET//TK-ZARF
SAP compartments
Special Access Programs (SAP) are created to control access, distribution, and protection of particularly sensitive information. Each SAP is identified by a nickname which consists of two unassociated, unclassified words or a single classified codeword. Such an identifier is abbreviated in a two or three-character designator.
There are apparently over 100 SAPs, with many having numerous compartments and sub-compartments. The classification line for SAP information shows the words SPECIAL ACCESS REQUIRED (SAR), followed by the program nickname or codeword. Examples of program nicknames are BUTTER POPCORN, MEDIAN BELL, SENIOR ICE and SODA.
In a classification line this is shown like: TOP SECRET//SAR-MEDIAN BELL
Multiple SAP's are shown like: TOP SECRET//SAR-MB/SAR-SD
SAP sub-compartmentsSubcompartments of SAPs are separated by spaces and they are listed in ascending alphabetic and numeric order. The classification markings do not show the hierarchy beyond the sub-compartment level. Sub-sub-compartments are listed in the same manner as sub-compartments.
In a classification line this is shown like: TOP SECRET//SAR-MB A691 D722
Dissemination markings
Dissemination markings or caveats are used to restrict the dissemination of information within only those people who have the appropriate clearance level and the need to know the information. Dissemination markings can also be used to control information which is unclassified. Some markings are used by multiple agencies, others are restricted to use by one agency.
Markings used by multiple agencies:
- FOR OFFICIAL USE ONLY (FOUO)
- SENSITIVE INFORMATION (SINFO)
Intelligence community markings:
- ORCON (OC)
- IMCON (IMC)
- SOURCES AND METHODS INFORMATION (SAMI)
- NOFORN (NF)
- PROPIN (PR)
- REL TO [country trigraph]
- RELIDO
- FISA
National Security Agency (NSA) markings:
- [country trigraph] EYES ONLY
National Geospatial intelligence Agency (NGA) markings:
- LIMDIS (DS)
- one undisclosed marking
Department of Defense (DoD) markings:
- NC2-ESI
- SPECAT (SC)
State Department (DoS) markings:
- EXDIS (XD)
- NODIS (ND)
- SENSITIVE BUT UNCLASSIFIED (SBU)
- SBU NOFORN
Drug Enforcement Administration (DEA) markings:
- DEA SENSITIVE (DSEN)
Nuclear weapons related markings:
- RESTRICTED DATA (RD)
- FORMERLY RESTRICTED DATA (FRD)
- DOD UNCLASSIFIED CONTROLLED NUCLEAR INFORMATION (DCNI)
- DOE UNCLASSIFIED CONTROLLED NUCLEAR INFORMATION (UCNI)
In a classification line this is shown like: SECRET//SI//ORCON
Multiple markings are shown like: SECRET//SI//ORCON/NOFORN
Nuclear weapons related markings
The markings Restricted Data (RD) and Former Restricted Data (FRD) are used by the Department of Defense and the Department of Energy for information about design and operation of nuclear warheads. Both can have the following two additional sub-markings:
- CRITICAL NUCLEAR WEAPON DESIGN INFORMATION (CNWDI)
- SIGMA (SG, followed by a number between 1 and 99)
In a classification line this is shown like: SECRET//RD-CNWDI
Multiple SIGMA markings are shown like: SECRET//RD-SIGMA 2-SIGMA 4
National Security Agency (NSA) markings
The Intelligence Community classification manual from 2009 lists four undisclosed dissemination markings which are used by the NSA. Maybe these are the same, or similar to a new kind of markings which were unveiled by the Snowden-leaks in 2013, but were already used in 2010. These markings are used to identify a COI, which apparently stands for Community Of Interest. COI identifiers are shown at the very end of a classification line.
Recently disclosed COI identifiers are:
- BULLRUN
- ENDUE
- NOCON (this could be an abbreviation of No Contractors)
In a classification line this is shown like: TOP SECRET//SI//NOFORN/BULLRUN
Links and Sources
- Wikipedia articles:
  - Classified information in the United States
  - Sensitive Compartmented Information
  - Special access program
- The 2010 Project BULLRUN Classification Guide
- The 2009 Intelligence Community Classification and Control Markings Implementation Manual (pdf)
- Article about Security Clearances and Classifications
- Some notes about Sensitive Compartmented Information
