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Clark & Parsia Releases Owlgres Reasoner

Posted on 2008-05-08

Clark & Parsia, LLC has completed the first release, version 0.1 (alpha), of Owlgres, a scalable reasoner for the OWL Web Ontology Language built on PostgreSQL. It implements DL-Lite, a tractable profile of the upcoming OWL 2 standard. Owlgres supports consistency checking and conjunctive query answering.

Downloads and documentation can be found at


The full release announcement is available at


Owlgres is dual-licensed; for open source projects, it’s available under the AGPL v.3. For commercial projects, commercial support licenses are available.

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