Sensitive Security Information or
SSI is sensitive but unclassified information obtained or developed in the conduct of security activities, the public disclosure of which would constitute an unwarranted invasion of privacy, reveal trade secrets or privileged or confidential information, or be detrimental to the security of transportation. It is not a form of classification under Executive Order 12958 as amended. SSI is
not classified national security information in the sense of Top Secret, Secret or Confidential. The safeguarding and sharing of SSI is governed by Title 49 Code of Federal Regulations (CFR) parts 15 and 1520. This designation is assigned to information to limit the exposure of the information to only those individuals that “
need to know” in order to participate in or oversee the protection of the nation’s transportation system. Those with a need to know can include persons outside of TSA, such as airport operators, aircraft operators, railroad carriers, rail hazardous materials shippers and receivers, vessel and maritime port owners and operators, foreign vessel owners, and other persons.