Is it necessary to import the ENTIRE OM-2 ontology?

[rpgoldman]

It would be better to import only what is needed, or even just reference ontology classes. If you bring the entire thing into your OWL ontology that means you are requiring any reasoner to process that entire ontology. This is both unnecessary and essentially impossible.

This issue arises because OWL does not have a notion of interface. Note that you can easily reference OM-2 URIs without needing to import the ontology.