12. Special Intelligence, or "SI," is an SCI control system designed to protect technical
and intelligence information derived from the monitoring of foreign communications signals by
other than the intended recipients. The SI control system protects  SI-derived information and
information relating to SI activities, capabilities, techniques, processes, and procedures.

[Another separate paragraph. SI is Special Intelligence, a control system to handle SCI, Special Compartmentalized Information. Man, keeping SI and SCI straight...]