- Racer : https://github.com/ha-mo-we/Racer/ released under the BSD-3 clause.
- Konclude : http://derivo.de/en/products/konclude/ released under the LGPL 2.1.
- SPARQL-DL : http://www.derivo.de/en/resources/sparql-dl-api/, https://www.w3.org/2001/sw/wiki/SPARQL-DL and https://github.com/protegeproject/sparql-dl-api released under the LGPL 3.0.