This 15 June 2012 article from the internal NSA newsletter SIDToday “SIGINT Philosopher” column tackles the subject of partial information: see the Intercept article The Philosopher of Surveillance, 11 August 2015.
This 6 September 2011 post from the NSA’s internal SIDToday newsletter describes progress in the agency’s speech-to-text capability over the course of the year: see the Intercept article The Computers are Listening: How the NSA Converts Spoken Words Into Searchable Text, 5 May 2015.
This NSA memo, dated 3 January 2011, draws analysts’ attention to a rule change, allowing “contact chaining, and other analysis, from and through any selector, irrespective of nationality and location, in order to follow or discover valid foreign intelligence targets”: see the New York Times article N.S.A. Gathers Data on Social Connections of U.S. Citizens, 28 September 2013.
This 13 September 2010 presentation from the NSA’s OTP VPN Exploitation Team explains the work of the division: see the Der Spiegel story Prying Eyes: Inside the NSA’s War on Internet Security, 28 December 2014.
This internal NSA post from 1 February 2006 describes the visit several agency personnel to bases in Germany: see the Der Spiegel article Spying Together: Germany’s Deep Cooperation with the NSA, 18 June 2014.
This May 2012 memo from the NSA’s International Crime and Narcotics division describes the operation of the MYSTIC system in the Bahamas and another, unnamed, country: see the Intercept article Data Pirates of the Caribbean: The NSA Is Recording Every Cell Phone Call in the Bahamas, 19 May 2014.
This internal NSA document from April 2013 gives background information to prepare for the then GCHQ Director’s visit on 30 April and 1 May; included topics include access to PRISM data, FLAME malware, Iran, Syria and Israel: see the Intercept article British Spy Chiefs Secretly Begged to Play in NSA’s Data Pools, 30 April 2014.
A series of casual posts written by a single author stationed in the NSA’s Signals Intelligence Directorate and posted on the agency’s intranet in 2012. Several posts written in December of that year describe the rationale and methodology of targeting systems administrators: see the Intercept article Inside the NSA’s Secret Efforts to Hunt and Hack System Administrators, 20 March 2014.
This internal NSA document from April 2013 provides a progress report on projects where the NSA’s Signals Intelligence Directorate (SID) strategy involves a foreign partner. A paragraph on Sweden indicates that GCHQ’s participation in Quantum malware operations “may be in jeopardy” but that making the project a joint US-Swedish one has been “NSA’s goal all along”: see the SVT article FRA part of top-secret hacker project, 11 December 2013.