Subject A can be any concept or entity outside of an ontology (or an ontology concept in a role of an entity being semantically annotated) that is (or is in a role of) 'Data', or an input, output, input or output argument of an 'Operation'. Object B can either be a concept that is a 'Format', or in unexpected cases an entity outside of an ontology that is a 'Format' or is in the role of a 'Format'. In EDAM, 'has_format' is not explicitly defined between EDAM concepts, only the inverse 'is_format_of'.