Top cited patent, US 5782181 references 27 US patents and is cited by seven other entities, as shown in the “How extensively has the top cited patent been built upon?” figure . The patent was issued in 1998 and just four years later in 2002, the time of this example study, there are ready two tiers of further investment. Three companies are working hard in this field. What the analysis team can conclude is that the assignees in this field are relatively concentrated and committed. This raises the question for the project team as to whether or not they can get support from their own management to enter this high investment area.