Government Protective Marking Scheme

Classified information in the United Kingdom is a system used to protect information from intentional or inadvertent release to unauthorised readers. The system is organised by the Cabinet Office and is implemented throughout central and local government and the critical national infrastructure. The system is also used by private sector bodies that provide services to the public sector.

The current classification system, the Government Security Classifications Policy, replaced the old Government Protective Marking Scheme in 2014. Since classifications can last for 100 years many documents written using the old scheme still exist and need protection. After that the classification may be of interest to historians.

Policy is set by the Cabinet Office. The Security Policy Framework (SPF) superseded the Manual of Protective Security and contains the primary internal protective security policy and guidance on security and risk management for Her Majesty's (HM) Government Departments and associated bodies. It is the source on which all localised security policies are based.

The classification system was formerly included in the Manual of Protective Security (MPS) which specified the impact of release and protection level required for each classification. Departments issued localised versions of the content of the MPS as appropriate to their operational needs.

The Cabinet Office issued the Government Security Classifications Policy in 2013; it came into effect in 2014. It replaced the old Government Protective Marking Scheme. Classifications must be capitalised and centrally noted at top and bottom of each document page, save at OFFICIAL where the document marking is optional. All material produced by a public body in the UK must be presumed to be OFFICIAL unless it is otherwise marked. Like the Protective Marking Scheme which it superseded, the GSCP classifications are applied only to the Confidentiality of the data under classification.

It is often incorrectly assumed that the OFFICIAL classification replaces the GPMS markings of PROTECT, RESTRICTED and CONFIDENTIAL, however this is not the case, since the criteria on which GPMS markings were applied bear no relationship to the criteria used for GSCP classifications.

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