Current Research

Patents, innovation, and economic development:

(part of the DFG-funded project "Patents and innovation in the German states, 1843-1877")

Working paper

The Consequences of Radical Patent-Regime Change (with Felix Selgert), 2022.

State: Preparing for submission.

Presentations: ASSA Virtual, 2022 (by co-author); University of York, 2021; EHA Virtual, 2020 (by co-author); EEA Virtual, 2020; VfS Leipzig, 2019; EHES Paris (by co-author), 2019; Munich Summer Institute, 2019; ZEW/MaCCI Conference Mannheim, 2019; BETA Workshop Strasbourg, 2019; GSWG Regensburg, 2019; University of Groningen, 2019; WEHC Boston, 2018; IP Day Boston University School of Law, 2018; Workshop "Business and the Law", University of Bayreuth, 2018; EHS Keele, 2018 (by co-author); University of Hohenheim, 2018; Workshop "Patent Law and Innovation", University of Bonn, 2018; University of Mannheim, 2017.

Awards: Best Paper Award Economic and Social History (GSWG Regensburg, 2019).

Abstract: We analyze the effect of patent-regime change on innovation by exploiting a quasi-natural experiment: the forced adoption of the Prussian patent system in territories annexed after the Austro-Prussian War of 1866. Compared to other German states, Prussia granted fewer patents because of a more rigorous technical examination and stricter novelty requirements. We use novel hand-collected data on patents and world's fair exhibits to test how the forced adoption of the more restrictive Prussian patent law affected innovation. More precisely, we use world’s fair exhibits as a proxy for non-patented innovation. First, we find that the forced adoption of the Prussian patent law caused a massive decline in patenting. Second, we find an increase in world’s fair exhibits per capita after the patent-regime change, suggesting that adopting the Prussian patent system was conducive to non-patented innovation. Finally, we show that increased technology diffusion is a plausible channel for the positive effect of patent-regime change on innovation.

Work in progress

The consequences of the division of Germany after the Second World War: 

(part of the DFG-funded project "Lack of economic freedom and innovation: Patent activities in the "Third Reich” and in the GDR")

Working paper

How the West was Settled. The Location Choice of East German Companies Migrating to West Germany after World War II (with Jochen Streb), 2023.

Presentations: University of Halle (by co-author); LSE, 2023 (by co-author); Universidad Carlos III de Madrid, 2013 (by co-author); GSWG Leipzig, 2023; University of Regensburg, 2023; Wirtschaftshistorischer Ausschuss des VfS, Bochum, 2022 (by co-author); University of Mannheim, 2022; HU Berlin, 2021 ; Baden-Württemberg Economic History Workshop Tübingen, 2021.

State: Preparing for submission.

Abstract: The division of Germany into a free-market West and a socialist East that followed the military defeat in spring 1945 induced thousands of East German companies to relocate to the West in the following years. This exogenous mass exodus allows us to identify the motives for the choice of firm location in a natural experiment. We test whether the East German firms were primarily attracted by existing West German agglomeration economies or rather sought new locations geographically close to their original homes, which allowed them to retain their access to pre-existing local networks. To test the determinants of the firms’ location choices, we use a newly constructed data set including information for over 4,200 relocated Eastern German firms, which we combine with county-level data on local economic activity and other socio-economic characteristics. By applying a mixed logit choice model, we find a negative effect of distance. Firms preferred places close to their original locations with market conditions they already knew. The fact that this negative distance effect is stronger for firms from original places close to the inner-German border strengthens our hypothesis that “home advantages” mattered. We also provide evidence for the attractiveness of agglomerations showing that firms favored places with high productivity and market potential. There are heterogeneous effects across industries: For companies in global market-oriented industries, the agglomeration effect is stronger and the location advantage smaller than for companies in industries with a more local customer or supplier base. 

Patenting, competition and conflict strategies:

(DFG reseach group "Conflict strategies in innovation markets (1850-1990)")

Working paper

Patent Litigation in the German Empire (with Felix Selgert and Jochen Streb), 2023.

Presentations: University of Mannheim, 2023; University of Oxford, 2023 (by co-author); GSWG Leipzig, 2023 (by co-author). 

State: Preparing for submission.

Abstract: We provide an empirical analysis of patent litigation in the German Empire by using a new data set that includes detailed information on patent proceedings. Our data combine micro-level information on nullification decisions by the Imperial Patent Office and the court of appeal, the Imperial Court, with data on high-value patents. By using nullification decisions as a proxy for patent conflicts, we analyze the differences in the intensity of patent conflicts across industries. Our results reveal a significant heterogeneity. By introducing the new concept of technological concentration, we show that in industries with high technological concentration patent litigation was less frequent. We argue that, unlike small and medium-sized enterprises, innovative companies with market power had the option of resolving patent disputes outside the courts through cartel-like agreements such as patent pools. 

Competition policy and competition in Germany:

Work in progress

German economy during the Weimar Republic:

Work in progress

Wealth inequality and persistence

Work in progress