Knowledge cumulability and complementarity in the knowledge generation function

This paper explores the role of external knowledge and internal stocks of knowledge in the generation of new technological knowledge. It relies on the notion of recombination and brings together three concepts: the appreciation of current expenses in R&D activities; the analysis of the role of the stock of knowledge composition; the identification of the role of external knowledge available in the regional proximity. The empirical section is based upon a panel of companies listed on the main European financial markets for the period 1995–2006. The econometric analysis considers patents as a measure of the knowledge out put and, on the right hand side, next to R&D expenditures, the stock of knowledge internal and external to each firm. The results confirm that the stock of internal knowledge and the access to external knowledge play a key role in assessing the actual capability of each firm to generate new knowledge.