Pushing the Limits of Reasoning over Ontologies with Hidden Content

There is currently a growing interest in techniques for hidi ng parts of the signature of an ontology Kh that is being reused by another ontology Kv. Towards this goal, Cuenca Grau, Motik, and Kazakov (2009) recently proposed the import-by- query framework, which makes the content of Kh accessi- ble through a limited query interface. If Kv reuses the sym- bols from Kh in a certain restricted way, one can reason over Kv ∪ Kh by accessing only Kv and the query interface. In this paper, we map out the landscape of the import-by-query problem. We show that certain restrictions of our original framework are strictly necessary to make reasoning possible; we propose extensions that overcome some of the expres- sivity limitations; we present several novel reasoning alg o- rithms; and we outline the limitations of the new framework.