In the past, non-practicing entities (NPEs) — firms that license patents without producing goods — have facilitated technology markets and increased rents for small inventors. Is this also true for today’s NPEs? Or are they “patent trolls” who opportunistically litigate over software...

This paper provides the first look at patent litigation hazards for public firms during the 80s and 90s. Consistent with our model, litigation is more likely when prospective defendants spend more on R&D, when prospective plaintiffs acquire more patents and when firms are larger and...

How much of the rapid growth in labor productivity in nineteenth century cotton weaving arose from capital-labor substitution and how much from technical change? Using an engineering production function and detailed information on inventions, I find that factor substitution accounts for little...

“Do Patents Facilitate Financing in the Software Industry?” by Ronald J. Mann contributes empirical evidence to our understanding of how software startups use patents. However, a close examination of the actual empirical findings in this paper points to rather different conclusions than...

Do patents provide critical incentives to encourage investment in innovation? Or, instead, do patents impose legal risks and burdens on innovators that discourage innovation, as some critics now claim? This paper reviews empirical economic evidence on how well patents perform as a property system.

A simple formal model shows that estimates of an upper bound on the value of firms' patent rents can be obtained from regressions on Tobin's Q. I test this model on a sample of US firms and find it is robust to a variety of considerations. The estimates correspond well with implied estimates...

Solow (1957) decomposed labor productivity growth into two components that are independent under Hicks neutrality: input growth and the residual, representing technical change. However, when technical change is Hicks biased, input growth is no longer independent of technical change, leading to...

This paper uses renewal data to estimate the value of U.S. patents, controlling for patent and owner characteristics. Estimates of U.S. patent value are substantially larger than estimates for European patents, however, the ratio of U.S. patent value to R&D for firms is only about 3%. Patents...

This paper estimates the total cost of patent litigation to alleged infringers. We use a large sample of stock market event studies around the date of lawsuit filings for US public firms from 1984-99. We find that the total costs of litigation are much greater than legal fees and costs are large...