Cosmic Top Secret [IAEA]

Sharing classified information between countries

When a government agency or group shares information between an agency or group of other country’s government they will generally employ a special classification scheme that both parties have previously agreed to honour.
For example, sensitive information shared amongst NATO allies has four levels of security classification; from most to least classified:

1. COSMIC TOP SECRET (CTS),
2. NATO SECRET (NS),
3. NATO CONFIDENTIAL (NC), and
4. NATO RESTRICTED (NR).

A special case exists with regard to NATO UNCLASSIFIED (NU) information. This is NATO property and must not be made public without NATO permission.
Another marking, ATOMAL, is applied to U.S. RESTRICTED DATA or FORMERLY RESTRICTED DATA and United Kingdom ATOMIC information that has been released to NATO. ATOMAL information is marked COSMIC TOP SECRET ATOMAL (CTSA), NATO SECRET ATOMAL (NSAT), or NATO CONFIDENTIAL ATOMAL (NCA).
In cases where a country wishes to share classified information bilaterally (or multilaterally) with a country that has a sharing agreement, the information is with the countries it can be shared with. Those countries would have to maintain the classification of the document at the level originally classified (TOP-SECRET, SECRET, etc.) with the appropriate caveat (USNZ, AUSGE, CANUK, etc.).

[edit] International organisations

• European Commission, has 5 levels, EU TOP SECRET, EU SECRET, EU CONFIDENTIAL, EU RESTRICTED, and EU COUNCIL / COMMISSION. [1] (Note that usually the French term is used)
• NATO, has 4 levels: COSMIC TOP SECRET (CTS), NATO SECRET (NS), NATO CONFIDENTIAL (NC), and NATO RESTRICTED (NR) [2]
• OCCAR, a European defence organisation, has three levels of classification: OCCAR SECRET, OCCAR CONFIDENTIAL, OCCAR RESTRICTED. [3].