 The core of the system is based around the proprietary Parallel Document Retrieval Engine (PADRE) developed by the Australian National University and CSIRO to perform very fast data look-ups.Its relevancy ranking system uses a variant of the Okapi BM25 algorithm to rank document content and metadata.The company has also been granted patents for annotation index methods (used for generating search result snippets) and search result sub-topic identification (used in Funnelback's Contextual Navigation system).