A method and a corresponding apparatus for inventoring software products on a plurality of computer are proposed. The inventoring system aims at populating a software catalog without the manual intervention of an administrator. The present invention reduces the cost of producing and maintaining a comprehensive knowledge base (the catalog) which contains definitions of software products and the related signature. Information about software products and their related signature is obtained through a process which gathers information from a potentially very large collection of computers. Any occurrence of a group of identical files across multiple computers is considered a reliable indicator that they belong to the installation footprint of a product.