Found when loading into Protege. Loading test case writes INFO to the log because hasDbXref, use in axiom annotations, is not declared as an annotation property. The axiom annotation do not appear when viewing, e.g., the class 'female organism'.

It's not clear to me what the right behavior is here. The spec says: "The axiom closure Ax of each OWL 2 DL ontology O MUST satisfy the typing constraints of OWL 2 DL." but then later says "Although declarations are not always required, they can be used to catch obvious errors in ontologies" suggesting ... declarations are not always required.

In this case the type should be inferred from the context - it is an axiom annotation and so the property should be understood as an annotation property.

   INFO  15:54:22  Unparsed triple: _:genid2147483649 -> http://www.geneontology.org/formats/oboInOwl#hasDbXref -> uk.ac.manchester.cs.owl.owlapi.OWLLiteralImplString@b4f3fce3
   INFO  15:54:22  Unparsed triple: _:genid2147483648 -> http://www.geneontology.org/formats/oboInOwl#hasDbXref -> uk.ac.manchester.cs.owl.owlapi.OWLLiteralImplString@b4f3fce3
   INFO  15:54:22  Unparsed triple: _:genid2147483650 -> http://www.geneontology.org/formats/oboInOwl#hasDbXref -> uk.ac.manchester.cs.owl.owlapi.OWLLiteralImplString@b4f3fce3