We formally analyze the effects of legal presumptions in patent litigation. We set up a novel contest model to study litigation outcomes, judgement errors, and resource dissipation under three alternative presumption criteria: a presumption that the patent is valid; a presumption that the patent...

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 patents...

Using new data on citations to university patents and scientific publications, and measures of distance based on Google maps, we study how geography affects university knowledge diffusion. We show that knowledge flows from patents are localized in two respects: they decline sharply with distance...

We study how fragmentation of patent rights ('patent thickets') and the formation of the Court of Appeal for the Federal Circuit (CAFC) affected the duration of patent disputes, and thus the speed of technology diffusion through licensing. We develop a model of patent litigation which predicts...

The paradigmatic defendant in a patent lawsuit is a vertically integrated manufacturer. But much economic activity is conducted collaboratively by a supply chain of vertically disintegrated firms, and sometimes multiple firms are implicated in infringing activities, by making, selling, or using...

Many standard setting organizations (SSOs) require participants to disclose patents that might be infringed by implementing a proposed standard, and commit to license their “essential” patents on terms that are at least fair, reasonable and non-discriminatory (FRAND). Data from these SSO...

Measuring patent value is an important goal of scholars in both patent law and patent economics. However, doing so objectively, accurately, and consistently has proved exceedingly difficult. At least part of the reason for this difficulty is that patents themselves are complex documents that are...

The progression toward reevaluating patent validity in the administrative, rather than judicial, setting became overtly substitutionary in the America Invents Act. No longer content to encourage court litigants to rely on Patent Office expertise for faster, cheaper, and more accurate validity...

The twenty-first century “patent litigation explosion” is not unprecedented. In fact, the nineteenth century saw an even bigger surge of patent cases. During that era, the most prolific patent enforcers brought hundreds or even thousands of suits, dwarfing the efforts of today's leading...

We show that examiner-driven variation in patent rights leads to quantitatively large impacts on several patent outcomes, including patent value, citations, and litigation. Notably, Patent Assertion Entities (PAEs) overwhelmingly purchase patents granted by "lenient" examiners. These examiners...