Restricted Data

Restricted Data (RD) is a category of proscribed information, per National Industrial Security Program Operating Manual (NISPOM).

The fact that its legal definition includes "all data" except that already specifically declassified has been interpreted to mean that atomic energy information in the United States is born classified, even if it was not created by any agency of the U.S.

In addition, a document containing Restricted Data could also contain Critical Nuclear Weapon Design Information (CNWDI).

It means that they have been downgraded specifically for the purpose of sharing among military agencies as "National Security Information".

It is defined as "Classified information which has been removed from the Restricted Data category after DOE and the Department of Defense have jointly determined that it relates primarily to the military utilization of atomic weapons, and can be adequately safeguarded as national security information.