Intelligence source

A person, organization, or technical means that provides foreign intelligence or foreign counterintelligence and that, if its identity or capability is disclosed, is vulnerable to counteraction that could nullify or significantly reduce its effectiveness in providing foreign intelligence or foreign counterintelligence to the United States. An intelligence source also means a person or organization that provides foreign intelligence or foreign counterintelligence to the United States only on the condition that its identity remains undisclosed.