America Online Inc has acquired Personal Library Software Inc, an information indexing and search technology company based in Rockville, Maryland, on undisclosed terms. Privately held PLS, a 12 year-old company, developed the core technology for search within the AOL service. In exchange for common stock, AOL will obtain PLS and its software products, which it says will secure the future of its key technology. It will continue to support existing PLS customers, which include AT&T Co, Dow Jones, the Washington Post, USA Today and Bertelsmann AG. The PLS technology includes post-Boolean retrieval tools, such as natural language querying, heuristic relevance ranking, and dynamic concept searching.
