Marking Classified Information

Physically marking classified information with appropriate classification and control markings serves to warn and inform holders of the degree of protection required. Other notations aid in derivative classification actions and facilitate downgrading or declassification. It is important that all classified information and material be marked to clearly convey the level of classification assigned, the portions that contain or reveal classified information, the period of time protection is required, and any other notations required for protection of the information or material.

The following is a summary of the most commonly used document control markings. More detailed information is available via the Internet from a variety of sources.1

Overall Classification Markings

The overall (i.e., highest) classification of a document is marked at the top and bottom of the outside cover (if there is one), the title page (if there is one), the first page, and the outside of the back cover (if there is one) or back side of the last page.

Each interior page containing classified information is marked top and bottom with the overall (i.e., highest) classification of the page. Each unclassified interior page is marked 'Unclassified" at the top and bottom. Interior pages that are For Official Use Only need to be marked only at the bottom. Blank pages require no markings.

Attachments and annexes may become separated from the basic document. They should be marked as if they were separate documents.

Additionally, every classified document must show, on the face of the document, the agency and office that created it and date of creation. This information must be clear enough to allow someone receiving the document to contact the preparing office if questions or problems about classification arise.

U.S. documents that contain foreign government information shall be marked on the front, "THIS DOCUMENT CONTAINS FOREIGN GOVERNMENT (indicate level) INFORMATION."

Computer files must be marked with appropriate headers and footers to ensure that anything that is transmitted or printed will have the applicable classification and associated markings.

All removable storage media and devices such as diskettes, CD-ROMs, cassettes, magnet tape reels, etc. must have an outer label with the appropriate markings.

Each slide must be marked on the slide itself or slide cover, as well as on the image that is projected.

Automated Information Processing Requirements

Use of automated information systems to route and control access to information is forcing changes in how documents are marked.  Within the Intelligence Community, classification and control markings must now follow a specified format that enables automated systems to recognize the markings.

The following formats apply only within the Intelligence Community.2 However, similar rules are under consideration in the Defense Department and other government organizations. 

Any classified document, either in hard copy or automated, must contain a header and footer with the classification, any control markings, and declassification date or designation. These three elements -- classification, control marking(s), and declassification date -- must be separated by two forward slashes and no spaces. If multiple dissemination control markings are used, they are separated by a comma and no spaces, except that multiple SCI controls are separated by a single forward slash and no spaces. Declassification date must be marked by an eight-digit number (year, month, day), exemption category (such as X1), or as Manual Review (MR). This is illustrated by the following examples:



A control marking such as FOR OFFICIAL USE ONLY cannot stand alone. It must be preceded by a classification as in:


When marking foreign government classified information, the classification is preceded by two forward slashes and countries are identified by an approved three-letter designator, as in //NATO SECRET or //DEU SECRET for Germany.  

Portion Marking

The title or subject of a classified document is marked with the appropriate classification abbreviation in parentheses -- (TS), (S), (C), or (U) immediately following and to the right of the title or subject.

Each section, part, paragraph, or similar portion of a classified document is to be marked with the appropriate classification abbreviation in parentheses immediately before the beginning of the portion. If the portion is numbered or lettered, place the abbreviation in parentheses between the letter or number and the start of the text.

Portions of U.S. documents containing foreign government information are marked to reflect the foreign country of origin as well as the appropriate classification, for example, (U.K.-C). Portions of U.S. documents containing extracts from NATO documents are marked to reflect "NATO" or "COSMIC" as well as the appropriate classification, for example, (NATO-S) or (COSMIC-TS). Further information is available at Foreign Government Classified Information.

Release to Foreign Countries/Organizations

In support of homeland security and coalition warfare, the U.S. Government has an increased need to share data with foreign countries, international organizations, and multinational forces. This has led to recent changes in the use of the "Released to..." (REL TO) control marking. This marking was previously only for use on intelligence information, but it is now authorized for use on all classified defense information.

Following the REL TO marking is a list of countries to which the information may be released through proper disclosure channels to specified foreign governments or international organizations. This list starts with USA and is followed by other countries listed alphabetically by the approved country code(s), international organization, or coalition force.


This format with // after the classification, a comma and space between each country, and with a lower case "and" with no comma before the last country code must be followed exactly to facilitate machine reading and sorting of the document. The approved three-letter country codes are available on the Internet at This marking shall appear at the top and bottom of the front cover (if there is one), the title page (if there is one), the first page and the outside of the back cover (if there is one). Each interior page containing classified information is marked top and bottom with the overall (i.e., highest) classification of the page.

When portion marking individual titles or paragraphs, the countries do not need to be listed unless they are different from the countries listed in the REL TO at the top and bottom of the page. For example: (TS:REL). If information is releasable to different countries than those listed in the overall REL TO marking, all the countries and organizations should be listed in the portion marking. For example: (S//REL TO USA, AUS, NZL and NATO).

The marking "Not Releasable to Foreign Nationals" (NOFORN) is still only authorized for use on intelligence that requires originator approval before being disclosed (see below).

Other Distribution Controls

In addition to its classification, intelligence information and certain scientific or technical information may also be subject to other controls on its distribution and handling. It is your responsibility to understand and comply with the control markings on classified information. If you are not sure, contact your security office. These control markings include:

  • Dissemination and Extraction of Information Controlled by Originator (ORCON) or (OC) means that any additional distribution or inclusion in another document must be approved by the originator of the document. It is used on intelligence information that could permit identification of a sensitive intelligence source or method.
  • Not Releasable to Contractors/Consultants (NOCONTRACT) has been discontinued but is still seen on older documents. Check with the originator of the document regarding any ongoing controls on the use of such a document.  This caveat was used on intelligence information that is provided by a source on the express or implied condition that it not be made available to contractors; or that, if disclosed to a contractor, would actually or potentially give him/her a competitive advantage or cause a conflict of interest with his/her obligation to protect the information.
  • Caution - Proprietary Information Involved (PROPIN) or (PR) is used with or without a security classification to identify information provided by a commercial firm or private source under an express or implied understanding that the information will be protected as a trade secret or proprietary data with actual value.
  • NOFORN is for intelligence information that may not be passed to foreign nationals.
  • Authorized for Release to ____ (REL TO) signifies intelligence information that is releasable to or has been released through proper disclosure channels to the named foreign government or international organization. See more specific guidance in previous section.
  • Sensitive Compartmented Information (SCI) applies to certain intelligence sources, methods, or analytical processes that are subject to a formal access control system established by the Director of Central Intelligence. Special approval is required for access to SCI.
  • Communications Security (COMSEC) is the protection of all elements of telecommunications -- encryption, transmission, emissions, and the physical security of equipment and materials.
  • Cryptographic Material (CRYPTO) identifies information or materials that must be handled through special cryptographic channels.
  • Warning Notice - Intelligence Sources or Methods Involved (WNINTEL) has been discontinued but is still seen on older documents.  It was used on intelligence information that identifies or would reasonably permit identification of an intelligence source or method that is susceptible to countermeasures that could nullify or reduce its effectiveness.
  • Critical Nuclear Weapons Design Information (CNWDI) or (N) applies to information that reveals the theory of operation or design of the components of a thermonuclear or fission bomb, warhead, demolition munition, or test device. Special handling procedures are required.

Department of Defense also uses the marking Alternative or Compensatory Control Measures (ACCM) for classified information that requires special security measures to safeguard classified intelligence or operations and support information when normal measures are insufficient to achieve strict need-to-know controls and where special access program (SAP) controls are not required. ACCM measures are defined as the maintenance of lists of personnel to whom the specific classified information has been or may be provided together with the use of an unclassified project nickname. The ACCM designation is used in conjunction with the security classification to identify the portion, page, or document containing ACCM information.

Related Topics: Classification Procedures, Foreign Government Classified Information.

1. Policy guidelines for the classification, marking, and declassification of national security information are found in the President's Executive Order 12958, Classified National Security Information, April 17, 1995. The full text of this order is available at the DSS web site,, as is the DoD Guide to Marking Classified Documents, DoD 5200.1-PH.  Classification and marking guidelines for defense industry are in Chapter 4 of the National Industrial Security Program Operating Manual.  The full text of the NISPOM is also available at the Defense Security Service Internet site, For non-DoD agencies, the Information Security Oversight Office publishes a free booklet entitled Marking with instructions and illustrations for marking classified documents.
2. Classification and control markings and country designators authorized for use by the Intelligence Community are compiled in the Authorized Classification and Control Markings Register maintained by the Community Management Staff.




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