Principles for Modifying an Existing Ontology Term
This page seems redundant with Deleting_Asserted_Subclasses Merge somehow ?
Terms can be moved as long as the term's new position correctly reflects its relationships to other terms and moving the term does not imply a significant change in the meaning of the term. Terms should not, however, be moved between ontologies; only within the same ontology. If you need to move a term to a different ontology, first obsolete it and then create a new term in the other ontology.