Interactive Overlay Maps for US Patent (USPTO) Data Based on   International Patent Classifications (IPC)
  We report on the development of an interface to the US Patent and Trademark Office (USPTO) that allows for the mapping of patent portfolios as overlays to basemaps constructed from citation relations among all patents contained in this database during the period 1976-2011. Both the interface and the data are in the public domain; the freeware programs VOSViewer and/or Pajek can be used for the visualization. These basemaps and overlays can be generated at both the 3-digit and 4-digit levels of the International Patent Classifications (IPC) of the World Intellectual Property Organization (WIPO). The basemaps can provide a stable mental framework for analysts to follow developments over searches for different years, which can be animated. The full flexibility of the advanced search engines of USPTO are available for generating sets of patents and/or patent applications which can thus be visualized and compared. This instrument allows for addressing questions about technological distance, diversity in portfolios, and animating the developments of both technologies and technological capacities of organizations over time. 
Loet Leydesdorff, Duncan Kushnir, and Ismael Rafols
cs.DL