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  • The January 2017 Beta release of the international SNOMED CT MRCM is now available to Members via SNOMED International's MLDS ( Others may request access by emailing the Release Management Team via SNOMED International's helpdesk service (, with the subject "Release Management Team - MRCM Beta access request". Please note that the Beta release package is distributed for evaluation purposes only. It must not be used in production clinical systems or in clinical settings. For more information, please visit SNOMED CT MRCM Refset Package Release Notes - January 2017.
  • A human-readable copy of the Beta release is also available at However, please note that this is provided purely for the purposes of evaluating the Beta release, and will not be supported beyond the Beta.
  • From July 2017, it is anticipated that the MRCM will be packaged as reference set files within the SNOMED CT international edition, and associated human-readable guidance will be available online.
  • To comment on the MRCM Beta release, please click on the Feedback button at the bottom of this page.
  • To comment on this document (i.e. the MRCM design specification), please click on the Feedback button on the bottom of the relevant page.
  • All feedback on the MRCM Beta must be submitted by Friday 31st March 2017.

The SNOMED CT Machine Readable Concept Model (MRCM) represents the SNOMED CT concept model rules in a form that can be read and tested by a computer. A human readable version of the SNOMED CT concept model can be found in the SNOMED CT Editorial Guide (, along with additional guidance for SNOMED CT authors.

This specification defines the format used by SNOMED International's MRCM. This format uses the SNOMED CT Reference Set mechanism to provide a file structure with inbuilt versioning, and the Expression Constraint Language to represent intensional SNOMED CT subsets referred to by the concept model rules. This allows distribution of the MRCM using standard RF2 reference set files and interpretation of the rules using tools that support the SNOMED CT Expression Constraint Language.

Latest web browsable version: 

SNOMED CT Document Library:

Publication date: 2017-05-28
This is the date when this PDF file was generated from the online version of this document.

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