2001.23—Classification marking in the electronic environment.

(a) General. Classified national security information in the electronic environment shall be:
(1) Subject to all requirements of the Order.
(2) Marked with proper classification markings to the extent that such marking is practical, including portion marking, overall classification, “Classified By,” “Derived From,” “Reason” for classification (originally classified information only), and “Declassify On.”
(3) Marked with proper classification markings when appearing in an electronic output (e.g., database query) in which users of the information will need to be alerted to the classification status of the information.
(4) Marked in accordance with derivative classification procedures, maintaining traceability of classification decisions to the original classification authority. In cases where classified information in an electronic environment cannot be marked in this manner, a warning shall be applied to alert users that the information may not be used as a source for derivative classification and providing a point of contact and instructions for users to receive further guidance on the use and classification of the information.
(5) Prohibited from use as source of derivative classification if it is dynamic in nature (e.g., wikis and blogs) and where information is not marked in accordance with the Order.
(b) Markings on classified e-mail messages. (1) E-mail transmitted on or prepared for transmission on classified systems or networks shall be configured to display the overall classification at the top and bottom of the body of each message. The overall classification marking string for the e-mail shall reflect the classification of the header and body of the message. This includes the subject line, the text of the e-mail, a classified signature block, attachments, included messages, and any other information conveyed in the body of the e-mail. A single linear text string showing the overall classification and markings shall be included in the first line of text and at the end of the body of the message after the signature block.
(2) Classified e-mail shall be portion marked. Each portion shall be marked to reflect the highest level of information contained in that portion. A text portion containing a uniform resource locator (URL) or reference (i.e., link) to another document shall be portion marked based on the classification of the content of the URL or link text, even if the content to which it points reflects a higher classification marking.
(3) A classified signature block shall be portion marked to reflect the highest classification level markings of the information contained in the signature block itself.
(4) Subject lines shall be portion marked to reflect the sensitivity of the information in the subject line itself and shall not reflect any classification markings for the e-mail content or attachments. Subject lines and titles shall be portion marked before the subject or title.
(5) For a classified e-mail, the classification authority block shall be placed after the signature block, but before the overall classification marking string at the end of the e-mail. These blocks may appear as single linear text strings instead of the traditional appearance of three lines of text.
(6) When forwarding or replying to an e-mail, individuals shall ensure that, in addition to the markings required for the content of the reply or forward e-mail itself, the markings shall reflect the overall classification and declassification instructions for the entire string of e-mails and attachments. This will include any newly drafted material, material received from previous senders, and any attachments.
(c) Marking Web pages with classified content. (1) Web pages shall be classified and marked on their own content regardless of the classification of the pages to which they link. Any presentation of information to which the web materials link shall also be marked based on its own content.
(2) The overall classification marking string for every web page shall reflect the overall classification markings (and any dissemination control or handling markings) for the information on that page. Linear text appearing on both the top and bottom of the page is acceptable.
(3) If any graphical representation is utilized, a text equivalent of the overall classification marking string shall be included in the hypertext statement and page metadata. This will enable users without graphic display to be aware of the classification level of the page and allows for the use of text translators.
(4) Classified Web pages shall be portion marked. Each portion shall be marked to reflect the highest level of information contained in that portion. A portion containing a URL or reference to another document shall be portion marked based on the classification of the content of the URL itself, even if the content to which it points reflects a higher classification marking.
(5) Classified Web pages shall include the classification authority block on either the top or bottom of the page. These blocks may appear as single linear text strings instead of the traditional appearance of three lines of text.
(6) Electronic media files such as video, audio, images, or slides shall carry the overall classification and classification authority block, unless the addition of such information would render them inoperable. In such cases, another procedure shall be used to ensure recipients are aware of the classification status of the information and the declassification instructions.
(d) Marking classified URLs. URLs provide unique addresses in the electronic environment for web content and shall be portion marked based on the classification of the content of the URL itself. The URL shall not be portion marked to reflect the classification of the content to which it points. URLs shall be developed at an unclassified level whenever possible. When a URL is classified, a classification portion mark shall be used in the text of the URL string in a way that does not make the URL inoperable to identify the URL as a classified portion in any textual references to that URL. An example may appear as:
http://www.center.xyz/SECRET/filename_(S).html
http://www.center.xyz/filename2_(TS).html
http://www.center.xyz/filename_(TS//NF).html
(e) Marking classified dynamic documents and relational databases. (1) A dynamic page contains electronic information derived from a changeable source or ad hoc query, such as a relational database. The classification levels of information returned may vary depending upon the specific request.
(2) If there is a mechanism for determining the actual classification markings for dynamic documents, the appropriate classification markings shall be applied to and displayed on the document. If such a mechanism does not exist, the default should be the highest level of information in the database and a warning shall be applied at the top of each page of the document. Such content shall not be used as a basis for derivative classification. An example of such an applied warning may appear as:
This content is classified at the [insert system-high classification level] level and may contain elements of information that are unclassified or classified at a lower level than the overall classification displayed. This content may not be used as a source of derivative classification; refer instead to the pertinent classification guide(s).
(3) This will alert the users of the information that there may be elements of information that may be either unclassified or classified at a lower level than the highest possible classification of the information returned. Users shall be encouraged to make further inquiries concerning the status of individual elements in order to avoid unnecessary classification and/or impediments to information sharing. Resources such as classification guides and points of contact shall be established to assist with these inquiries.
(4) Users developing a document based on query results from a database must properly mark the document in accordance with § 2001.22. If there is doubt about the correct markings, users should contact the database originating agency for guidance.
(f) Marking classified bulletin board postings and blogs. (1) A blog, an abbreviation of the term “web log,” is a Web site consisting of a series of entries, often commentary, description of events, or other material such as graphics or video, created by the same individual as in a journal or by many individuals. While the content of the overall blog is dynamic, entries are generally static in nature.
(2) The overall classification marking string for every bulletin board or blog shall reflect the overall classification markings for the highest level of information allowed in that space. Linear text appearing on both the top and bottom of the page is acceptable.
(3) Subject lines of bulletin board postings, blog entries, or comments shall be portion marked to reflect the sensitivity of the information in the subject line itself, not the content of the post.
(4) The overall classification marking string for the bulletin board posting, blog entry, or comment shall reflect the classification markings for the subject line, the text of the posting, and any other information in the posting. These strings shall be entered manually or utilizing an electronic classification tool in the first line of text and at the end of the body of the posting. These strings may appear as single linear text.
(5) Bulletin board postings, blog entries, or comments shall be portion marked. Each portion shall be marked to reflect the highest level of information contained in that portion.
(g) Marking classified wikis. (1) Initial wiki submissions shall include the overall classification marking string, portion marking, and the classification authority block string in the same manner as mentioned above for bulletin boards and blogs. All of these strings may appear as single line text.
(2) When users modify existing entries which alter the classification level of the content or add new content, they shall change the required markings to reflect the classification markings for the resulting information. Systems shall provide a means to log the identity of each user, the changes made, and the time and date of each change.
(3) Wiki articles and entries shall be portion marked. Each portion shall be marked to reflect the highest level of information contained in that portion.
(h) Instant messaging, chat, and chat rooms. (1) Instant messages and chat conversations generally consist of brief textual messages but may also include URLs, images, or graphics. Chat discussions captured for retention or printing shall be marked at the top and bottom of each page with the overall classification reflecting all of the information within the discussion and, for classified discussions, portion markings and the classification authority block string shall also appear.
(2) Chat rooms shall display system-high overall classification markings and shall contain instructions informing users that the information may not be used as a source for derivative classification unless it is portion marked, contains an overall classification marking, and a classification authority block.
(i) Attached files. When files are attached to another electronic message or document, the overall classification of the message or document shall account for the classification level of the attachment and the message or document shall be marked in accordance with § 2001.24(b).
(ii) Reserved.