Change of claim structures of market leaders' Japanese published unexamined patent applications according to the degree of technology maturity

This paper analyses claim structures of Japanese published unexamined patent applications on digital camera filed by firms participating in the Japanese market of digital camera for each of the stages from the innovator stage to the late majority stage and investigates the contribution of claim structures to capture of market share for each stage. A main finding is that claim structures reflect the life-cycle stages of a product. The market leader of the early adopter stage filed patent applications having more independent claims of which the claim category is 'digital camera' or the like compared to the rest of the participating firms, while the market leader of the late majority stage has more dependent claims. This indicates that it is critical to cover a maximal scope of the invention by plural independent claims in the early adopter stage, while, in the late majority stage in which the technologies are highly matured, the total number of dependent claims are increased to protect the market leader's technologies against competitors and as a means of fallback options.