Joan Farre-Mensa

Harvard Business School
Rock Center 218
Boston, MA 02163

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NBER Working Papers and Publications

March 2017What is a Patent Worth? Evidence from the U.S. Patent “Lottery”
with Deepak Hegde, Alexander Ljungqvist: w23268
We provide evidence on the value of patents to startups by leveraging the random assignment of applications to examiners with different propensities to grant patents. Using unique data on all first-time applications filed at the U.S. Patent Office since 2001, we find that startups that win the patent “lottery” by drawing lenient examiners have, on average, 55% higher employment growth and 80% higher sales growth five years later. Patent winners also pursue more, and higher quality, follow-on innovation. Winning a first patent boosts a startup’s subsequent growth and innovation by facilitating access to funding from VCs, banks, and public investors.
February 2016The Bright Side of Patents
with Deepak Hegde, Alexander Ljungqvist: w21959
Motivated by concerns that the patent system is hindering innovation, particularly for small inventors, this study investigates the bright side of patents. We examine whether patents help startups grow and succeed using detailed micro data on all patent applications filed by startups at the U.S. Patent and Trademark Office (USPTO) since 2001 and approved or rejected before 2014. We leverage the fact that patent applications are assigned quasi-randomly to USPTO examiners and instrument for the probability that an application is approved with individual examiners’ historical approval rates. We find that patent approvals help startups create jobs, grow their sales, innovate, and reward their investors. Exogenous delays in the patent examination process significantly reduce firm growth, job cr...
October 2013Do Measures of Financial Constraints Measure Financial Constraints?
with Alexander Ljungqvist: w19551
Financial constraints are not directly observable, so empirical research relies on indirect measures. We evaluate how well five popular measures (paying dividends, having a credit rating, and the Kaplan-Zingales, Whited-Wu, and Hadlock-Pierce indices) identify firms that are financially constrained, using three novel tests: an exogenous increase in a firm's demand for credit; exogenous variation in the supply of bank loans; and the tendency for firms to pay out the proceeds of equity issues to their shareholders ("equity recycling"). We find that none of the five measures identifies firms that behave as if they were constrained: public firms classified as constrained have no trouble raising debt when their demand for debt increases, are unaffected by changes in the supply of bank loans, an...

Published: Joan Farre-Mensa & Alexander Ljungqvist, 2016. "Do Measures of Financial Constraints Measure Financial Constraints?," Review of Financial Studies, Society for Financial Studies, vol. 29(2), pages 271-308. citation courtesy of

September 2011Comparing the Investment Behavior of Public and Private Firms
with John Asker, Alexander Ljungqvist: w17394
We evaluate differences in investment behavior between stock market listed and privately held firms in the U.S. using a rich new data source on private firms. Listed firms invest less and are less responsive to changes in investment opportunities compared to observably similar, matched private firms, especially in industries in which stock prices are particularly sensitive to current earnings. These differences do not appear to be due to unobserved differences between public and private firms, how we measure investment opportunities, lifecycle differences, or our matching criteria. We suggest that the patterns we document are most consistent with theoretical models emphasizing the role of managerial myopia.
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