Identifiers provided by the Code System owner are authoritative, are intellectual property and provide a stable identifier for use in HL7 artifacts.  The authoritative identifier MUST be used for any new use of the Code System - this includes draft specifications as well as renewed or updated balloted artifacts.  If a Code System Identifier is used in a balloted HL7 artifact, and it is discovered that the Code System identifier is not correct, it must be changed when the specification is updated. 

HL7 must provide the means by which updated Code System Identifiers, either declared by the Code System Owner, or as a result of HL7 internal processes, are published and supported.  

FLAG.   This policy is under review by counsel as pertains to ownership and IP control over identifiers for code systems.   Depending upon the outcome of the legal review this policy may undergo revision (in spite of the fact that the vocabulary WG voted to approve this policy.

Next Steps documented here Co-chair minutes 7/14/2020 and here 2020-07-28 Vocab Chair Agenda/Minutes

Policy statement agreed on 8/11/2020

Meetings and related documents:

*Approved by Vocab and HTA on 5/20/2020

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  1. A few comments:

    1. Throughout the document there are references to ""Code System Identifiers", "URIs", "Identifier", "Authoritative Identifier", "Canonical URLs", "URLs" and "Code System URLs" which are all valid and shades of the same thing, but to the uninitiated, could be difficult to understand. To address this I suggest:
      1. The policy statement refer to the same concept from the title i.e. Code System Identifiers; and
      2. The background section defines all these concepts and synonyms; and
      3. The rest of the document sticks to using Code System Identifier to ease understanding.
    2. To avoid misunderstandings, I suggest the statement "Vocabulary owns the Code System resources." be updated to clarify whether the intended meaning is:
      1. Vocabulary Work Group owns and maintains the CodeSystem FHIR resources (e.g. stubs or authorised full FHIR CodeSystem instances) associated with these external code systems in UTG; or
      2. Vocabulary Work Group curates the FHIR CodeSystem resource type; or
      3. Something else;
    3. In relation to the statement "When a canonical URL for a Code System external to HL7 is not yet defined here, implementers MUST...",
      1. the link pointed to by "here" is to the HTA External Terminology Owner Engagement Process. This page does not actually contain definition of canonical URLs. Was this perhaps a typo and should be a reference to the External Terminologies - Information page?
      2. Some content should be added to address the cases where the external code system has a canonical URL defined in the following alternative places:
        1. UTG;
        2. The FHIR Specification;
        3. The HL7 OID registry;
        4. Resources available directly from the code system owner.
    4. For step 1 in the process ("Use terminology.hl7.org as a default/temporary domain in the Code System canonical URL"), could this rather be requested and assigned by Vocabulary Work Group rather specification authors doing so by themselves? That way, we can head off situations where an endorsed URL is already available for specification authors to use and also ensure the temporarily assigned one meets our stated requirements for Code System Canonical URLs.
    5. For step 2 ("Contact HTA to obtain an official canonical URL. HL7 will publish the authoritative or HL7 default identifier as preferred."), should the process not be follow the HTA External Terminology Owner Engagement Process as specified? 
  2. Reuben Daniels make your changes in-line. leave the comment as rationale for further discussion.