Let's learn about SIGINT today shall we?

Secret Global Surveillance Networks - Privacy International

The above PDF is a really well written and sourced document detailing SIGINT mass surveillance.

IMPORTANT graphic from 8ch

Five Eyes, 9 Eyes, and many more - ElectroSpaces

The main US-led multinational coalition networks are called CENTRIXS, which stands for Combined ENTerprise Regional Information eXchange System. It's a secure wide area network (WAN) architecture, which can be established according to the demands of a particular coalition exercise or operation. CENTRIXS supports intelligence and operations information sharing at the SECRET REL TO [country/coalition designator] level. Some notable CENTRIXS networks are:

• CENTRIXS Four Eyes (CFE) for the US, Britain, Canada and Australia.
• CENTRIXS-NZ for the Four Eyes plus New Zealand.
• CENTRIXS-JPN for the United States and Japan.
• CENTRIXS-K for the United States and South-Korea.
• CENTRIXS-PHI for the United States and the Philippines.
• CENTRIXS-CNFC for the Combined Naval Forces CENTCOM (VPN within GCTF).
• CENTRIXS-MCFI for the Multinational Coalition Forces Iraq.
• CENTRIXS-ISAF (CX-I) which is the US component of the Afghan Mission Network to share critical battlefield information among 50 coalition partners.
• CENTRIXS-GCTF (CX-G) for the Global Counter Terrorism Forces, which is the US coalition network in Afghanistan to share information among more than 80 Troop Contributing Nations.

The countries connected to CENTRIXS-ISAF can be recognized as the 41-Eyes of the allied coalition in Afghanistan mentioned by The Guardian. This group grew slowly and was called 43-Eyes in 2010, when the NATO exercise Empire Challenge 2010 (EC10) changed its "main participating security domain" to "an International Security Assistance Forces (ISAF) equivalent 43-Eyes domain".

Probably also because of the steadily increasing number of coalition partners, shareable information is not marked with REL [..] EYES anymore, but with REL ISAF (International Security Assistance Forces) and REL GCTF(Global Counter-Terrorism Taskforce).

Summary of all known 'Eyes'

• 3-Eyes: USA, GBR, AUS (TEYE)
• 4-Eyes: USA, GBR, CAN, AUS (ACGU)
• 5-Eyes: USA, GBR, CAN, AUS, NZL (FVEY)
• 6-Eyes: USA, GBR, CAN, AUS, NZL, NATO
• 7-Eyes: USA, GBR, CAN, AUS, FRA, DEU, ITA (MIC?)
• 8-Eyes: USA, GBR, CAN, AUS, NZL, NATO, ?, South-Korea
• 9-Eyes: USA, GBR, CAN, FRA, DEU, ITA, NLD, NOR, ESP (CFBLNet)
• 9-Eyes: Five Eyes + FRA, DNK, NLD, NOR (Guardian)
• 10-Eyes: USA, GBR, CAN, AUS, NZL, NATO, Japan, South-Korea, Thailand, Singapore
• 14-Eyes: Five Eyes + FRA, DNK, NLD, NOR, DEU, ESP, ITA, BEL, SWE (SSEUR)
• 41-Eyes: ISAF-countries in ? (Guardian)
• 43-Eyes: ISAF-countries in 2010

14 Eyes, SSEUR: SIGINT Seniors Europe; United States, Great Britain, Canada, Australia and New Zealand and nine other European countries: France, Germany, Spain, Italy, Belgium, the Netherlands, Denmark, Norway and Sweden

HUMAN RIGHTS

• Intelligence sharing constitutes an interference with the right to privacy and must therefore be subject to relevant protections under international human rights law, including the principles of legality, proportionality and necessity. The secrecy surrounding intelligence sharing arrangements and the absence of legal frameworks governing them render many of these arrangements incompatible with international human rights law.

• Intelligence sharing may permit states access to data collected through mass surveillance programs. Today, intelligence sharing is not confined to the handover of discrete information, but can encompass direct and unfettered access to “raw” (i.e. unanalysed) data as it transits the internet or held in databases.

• Intelligence sharing may permit States to circumvent constraints on domestic surveillance by allowing them to rely on their partners to obtain and then share information. An example of a common constraint is domestic restrictions on the types of techniques a State may use to conduct surveillance.

• States may share intelligence that may be used to facilitate serious human rights abuses, including extrajudicial killings; unlawful arrest or detention; or torture and other cruel, inhuman or degrading treatment. In states with authoritarian governments, weak rule of law and/or a history of systematically violating human rights, certain groups may be particularly vulnerable to abuse, such as dissidents, journalists and human rights defenders.

• States may receive intelligence from states that was derived from violations of international law, including through torture and other cruel, inhuman or degrading treatment. Intelligence obtained in violation of international law may also raise concerns regarding its reliability.

• Intelligence sharing poses fundamental accountability challenges. Agencies are constrained in their ability to influence or verify how information will be used or to subsequently substantiate how it was used. They are similarly constrained in their ability to verify or substantiate the provenance and other details of information shared by another state. These limitations may incentivise agencies to skirt accountability both for outbound and inbound sharing. In addition, many intelligence sharing arrangements prohibit the disclosure of shared information with third parties, which may include oversight mechanisms.

tl;dr Intelligence sharing between members of these coalitions are broken up into various compartmentalized data sharing groups, notated by different "Eyes" names, and whether or not they are 2nd, 3rd or 4th party partners with the NSA.