From what I see, US patent 6,904,428 (by the Illinois Institute of Technology) is a search algorithm process. Any ideas why IBM thought they needed it?
An intranet mediator for obtaining direct answers to natural language questions allowing users to search both a data warehouse of integrated/structured data sources and unstructured data sources. The intranet mediator allows the user to obtain an answer to a natural language question without having to surf the data sources in which the answer might be contained, or without being limited to one specific factual item return. The intranet mediator operates on the supposition that most answers to business queries are contained within structured data sources which have been integrated into the data warehouse thereby having common schema and known contents. Preselection of the most relevant data source(s) is thus possible before query output. Search of unstructured data is also performed for additional context surrounding either the question or the answer. A direct answer is given in response to the question. If desired, the intranet mediator may also display a list of data sources where additional relevant information may be found.