Vania Sena

University of Essex
Southend Campus Elmer Approach
Southend-on-Sea SS1 1LW
United Kingdom

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Institutional Affiliation: University of Essex

NBER Working Papers and Publications

September 2014Appropriability Mechanisms, Innovation and Productivity: Evidence from the UK
with Bronwyn H. Hall: w20514
We use an extended version of the well-established Crepon, Duguet and Mairesse model (1998) to model the relationship between appropriability mechanisms, innovation and firm-level productivity. We enrich this model in several ways. First, we consider different types of innovation spending and study the differences in estimates when innovation spending (rather than R&D spending) is used to predict innovation in the CDM model. Second, we assume that a firm simultaneously innovates and chooses among different appropriability methods (formal or informal) to protect the innovation. Finally, in the third stage, we estimate the impact of the innovation output conditional on the choice of appropriability mechanisms on firms' productivity. We find that firms that innovate and rate formal methods fo...

forthcoming in Economics of Innovation and New Technology citation courtesy of

May 2013The Importance (or not) of Patents to UK Firms
with Bronwyn H. Hall, Christian Helmers, Mark Rogers: w19089
A surprisingly small number of innovative firms use the patent system. In the UK, the share of firms patenting among those reporting that they have innovated is about 4%. Survey data from the same firms support the idea that they do not consider patents or other forms of registered IP as important as informal IP for protecting inventions. We show that there are a number of explanations for these findings: most firms are SMEs, many innovations are new to the firm, but not to the market, and many sectors are not patent active. We find evidence pointing to a positive association between patenting and innovative performance measured as turnover due to innovation, but not between patenting and subsequent employment growth. The analysis relies on a new integrated dataset for the UK that combines...

Published: Bronwyn H. Hall & Christian Helmers & Mark Rogers & Vania Sena, 2013. "The importance (or not) of patents to UK firms," Oxford Economic Papers, Oxford University Press, vol. 65(3), pages 603-629, July. citation courtesy of

April 2012The Choice between Formal and Informal Intellectual Property: A Literature Review
with Bronwyn H. Hall, Christian Helmers, Mark Rogers: w17983
We survey the economic literature, both theoretical and empirical, on the choice of intellectual property protection by firms. Our focus is on the tradeoffs between using patents and disclosing versus the use of secrecy, although we also look briefly at the use of other means of formal intellectual property protection.

Published: Bronwyn Hall, Christian Helmers, Mark Rogers, Vania Sena “The Choice between Formal and Informal Intellectual Property: A Review.” Journal of Economic Literature, Vol. 52, No. 2, June 2014 (pp. 375-423)

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