The http://purl.obolibary.org/obo/bfo/classes-only.owl variant of BFO ("bfo_classes_only.owl") includes only the class hierarchy and annotations from the full OWL version of BFO 2: http://purl.obolibary.org/obo/bfo.owl ("bfo.owl"). There are no object properties or logical axioms that use the object properties in bfo_classes_only.owl. As the logical axioms in the bfo_classes_only.owl variant are limited to subclass and disjoint assertions they are much weaker than the logical axioms in bfo.owl. If you plan to use the relations that define BFO 2, you should import bfo.owl instead of bfo_classes_only.owl. To the extent that the relations are used without importing bfo.owl, be mindful that they should be used in a manner consistent with their use in bfo.owl. Otherwise if your ontology is imported by a another ontology that imports bfo.owl there may be inconsistencies. See the BFO 2 release notes for further information about BFO 2. Please note that the current release of bfo.owl uses temporal relations when the subject or object is a continuant, a major change from BFO 1.
The Allotrope Foundation® Ontologies (“AFO”) is a curated collection of defined terms prepared by Allotrope Foundation. The AFO is collectively licensed under the Creative Commons Attribution License (CC-BY). However, the collection includes terms that are from or based on third party sources, as identified in the release notes, as updated from time-to-time. Such individual terms may be subject to subject to other licenses specified by the source (e.g., terms from the CHMO or chemical methods ontology are also under the CC-BY, while terms based on Wikipedia entries are subject to CC BY-SA).
This is an early version of BFO version 2 and has not yet been extensively reviewed by the project team members. Please see the project site http://code.google.com/p/bfo/ , the bfo2 owl discussion group http://groups.google.com/group/bfo-owl-devel , the bfo2 discussion group http://groups.google.com/group/bfo-devel, the tracking google doc http://goo.gl/IlrEE, and the current version of the bfo2 reference http://purl.obolibrary.org/obo/bfo/dev/bfo2-reference.docx . This ontology is generated from a specification at http://bfo.googlecode.com/svn/trunk/src/ontology/owl-group/specification/ and with the code that generates the OWL version in http://bfo.googlecode.com/svn/trunk/src/tools/. A very early version of BFO version 2 in CLIF is at http://purl.obolibrary.org/obo/bfo/dev/bfo.clif