History annotations allowed on all elements

The SBML Level 2 specification stipulates (in Section 6) that model history annotation (i.e., those involving dcterms:modified, vCard, and other similar content) are only permitted on the <model> element. Following requests to allow such content anywhere, the Level 3 specification does not limit history annotations in this way.

Changes relative to SBML Level 2

The basic change is that the [HISTORY] content in the template below will not be restricted to appearing only on <model> elements.

<SBML_ELEMENT +++ metaid="SBML_META_ID" +++ > 
  +++ 
  <annotation> 
    +++ 
    <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" 
             xmlns:dc="http://purl.org/dc/elements/1.1/" 
             xmlns:dcterm="http://purl.org/dc/terms/" 
             xmlns:vcard="http://www.w3.org/2001/vcard-rdf/3.0#" 
             xmlns:bqbiol="http://biomodels.net/biology-qualifiers/" 
             xmlns:bqmodel="http://biomodels.net/model-qualifiers/" 
    > 
      <rdf:Description rdf:about="#SBML_META_ID"> 
        [HISTORY] 
        <RELATION_ELEMENT> 
          <rdf:Bag> 
            <rdf:li rdf:resource="URI" /> 
            ... 
          </rdf:Bag> 
        </RELATION_ELEMENT> 
        ... 
      </rdf:Description> 
      +++ 
    </rdf:RDF> 
    +++ 
  </annotation> 
  +++ 
</SBML_ELEMENT> 

Notable implications

This has still-uncertain implications for software tools attempting to determine the latest change to a given SBML file. The fact that the history content may appear anywhere means that a subelement of <model> may contain more recent revision history data than the <model> element itself, forcing software tools to perform searches and comparisons when trying to determine such things as the latest timestamp left in a model.