Patent quality, cumulative innovation and market value: Evidence from Japanese firm level panel data

We examine empirically how patent quality in terms of forward citation and science linkage affect the market value of a firm. We find that both indicators affect the market value of a firm significantly even if we extensively control the effects of the other major determinants of the market value, including R&D investment and current return on asset. In addition, the forward citation affects the market value more in cumulative innovation area such as in IT, consistent with a theoretical proposition that the value of having a dependent patent is larger in the industry where innovation is cumulative among firms.