The Traffic Light Protocol (TLP) was created in order to facilitate greater sharing of information. TLP is a set of designations used to ensure that sensitive information is shared with the appropriate audience. It employs four colors to indicate expected sharing boundaries to be applied by the recipient(s). TLP only has four colors; any designations not listed in this standard are not considered valid by FIRST.
TLP provides a simple and intuitive schema for indicating when and how sensitive information can be shared, facilitating more frequent and effective collaboration. TLP is not a “control marking” or classification scheme. TLP was not designed to handle licensing terms, handling and encryption rules, and restrictions on action or instrumentation of information. TLP labels and their definitions are not intended to have any effect on freedom of information or “sunshine” laws in any jurisdiction.
TLP is optimized for ease of adoption, human readability and person-to-person sharing; it may be used in automated sharing exchanges, but is not optimized for that use.
TLP is distinct from the Chatham House rule (when a meeting, or part thereof, is held under the Chatham House Rule, participants are free to use the information received, but neither the identity nor the affiliation of the speaker(s), nor that of any other participant, may be revealed.), but may be used in conjunction if it is deemed appropriate by participants in an information exchange.
The source is responsible for ensuring that recipients of TLP information understand and can follow TLP sharing guidance.
If a recipient needs to share the information more widely than indicated by the original TLP designation, they must obtain explicit permission from the original source.
How to use TLP in email
TLP-designated email correspondence should indicate the TLP color of the information in the Subject line and in the body of the email, prior to the designated information itself. The TLP color must be in capital letters: TLP:RED, TLP:AMBER, TLP:GREEN, or TLP:WHITE.
- How to use TLP in documents
TLP-designated documents should indicate the TLP color of the information in the header and footer of each page. To avoid confusion with existing control marking schemes, it is advisable to right-justify TLP designations. The TLP color should appear in capital letters and in 12 point type or greater.
TLP:RED : R=255 , G=0 , B=51 , background: R=0, G=0, B=0
TLP:AMBER : R=255 , G=192 , B=0 , background: R=0, G=0, B=0
TLP:GREEN : R=51 , G=255 , B=0 , background: R=0, G=0, B=0
TLP:WHITE : R=255 , G=255 , B=255 , background: R=0, G=0, B=0
TLP:RED : C=0 , M=100 , Y=79 , K=0 , background: C=0, M=0, Y=0, K=100
TLP:AMBER : C=0 , M=25 , Y=100 , K=0 , background: C=0, M=0, Y=0, K=100
TLP:GREEN : C=79 , M=0 , Y=100 , K=0 , background: C=0, M=0, Y=0, K=100
TLP:WHITE : C=0 , M=0 , Y=0 , K=0 , background: C=0, M=0, Y=0, K=100
Not for disclosure, restricted to participants only. Sources may use TLP:RED when information cannot be effectively acted upon by additional parties, and could lead to impacts on a party's privacy, reputation, or operations if misused. Recipients may not share TLP:RED information with any parties outside of the specific exchange, meeting, or conversation in which it was originally disclosed. In the context of a meeting, for example, TLP:RED information is limited to those present at the meeting. In most circumstances, TLP:RED should be exchanged verbally or in person.
Limited disclosure, restricted to participants’ organizations.Sources may use TLP:AMBER when information requires support to be effectively acted upon, yet carries risks to privacy, reputation, or operations if shared outside of the organizations involved. Recipients may only share TLP:AMBER information with members of their own organization, and with clients or customers who need to know the information to protect themselves or prevent further harm. Sources are at liberty to specify additional intended limits of the sharing: these must be adhered to.
Limited disclosure, restricted to the community.Sources may use TLP:GREEN when information is useful for the awareness of all participating organizations as well as with peers within the broader community or sector. Recipients may share TLP:GREEN information with peers and partner organizations within their sector or community, but not via publicly accessible channels. Information in this category can be circulated widely within a particular community. TLP:GREEN information may not released outside of the community.
Disclosure is not limited. Sources may use TLP:WHITE when information carries minimal or no foreseeable risk of misuse, in accordance with applicable rules and procedures for public release. Subject to standard copyright rules, TLP:WHITE information may be distributed without restriction.
 First.org , TRAFFIC LIGHT PROTOCOL (TLP) FIRST Standards Definitions and Usage Guidance — Version 1.0 , viewed 29 March 2019, https://www.europol.europa.eu/sites/default/files/documents/common_taxonomy_for_law_enforcement_and_csirts_v1.3.pdf