If certain information within a classified document is portion marked as TS//RD-N, what type of information does it indicate?

The designation TS//RD-N indicates that the information is classified at the Top Secret level and specifically relates to Restricted Data concerning nuclear weapons. The inclusion of "RD" denotes that the information falls under the category of Restricted Data, which is primarily associated with atomic and nuclear energy information, including the design and functioning of nuclear weapons. The "N" implies that it pertains to nuclear information, reinforcing that this is highly sensitive information critical to national security.

In this context, the information marked as TS//RD-N is not merely general sensitive information or operational plans; it is specifically critical nuclear weapon design information (CNWDI), which is tightly controlled and has significant implications for national defense and security operations. The nature of CNWDI means that any unauthorized disclosure could jeopardize national security, making the proper handling and marking of such information imperative.