12.05.2026 • 14/2026
Einladung und Veranstaltungshinweis: Wie frei ist Europas Wissenschaft?
Radikale Akteure, geopolitische Spannungen und Sparvorgaben belasten die Wissenschaft weltweit. Wie die Wissenschaftsfreiheit bei uns wieder gestärkt werden kann, diskutieren Experten unterschiedlicher Disziplinen mit dem Publikum am 27. Mai 2026 ab 18 Uhr in der Leopoldina in Halle (Saale). Zu dieser siebten Europa-Debatte mit Empfang laden das Leibniz-Institut für Wirtschaftsforschung Halle (IWH) und die Leopoldina Sie herzlich ein. Wir bitten um eine redaktionelle Ankündigung.
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Common Ownership, Tacit Know-How, and the Market for Technology
Dennis Hutschenreiter
IWH Discussion Papers,
No. 3,
2026
Abstract
Firms increasingly rely on markets for technology to acquire innovations developed outside their boundaries, yet acquiring intellectual property rights alone often does not guarantee successful implementation. Many technologies depend on tacit know-how that must be supplied by the provider after the transaction is completed. This paper examines whether common ownership between a technology provider and a potential adopter mitigates this implementation problem. I develop a model in which overlapping institutional investors cause the provider to partially internalize the adopter’s gains from successful implementation, strengthening incentives to transfer tacit know-how. This mechanism operates only when know-how is unverifiable – absent this friction, common ownership leaves matching and outcomes unchanged. Under moral hazard, the model predicts that common ownership increases the likelihood of technology transfer to a given adopter, that this effect is stronger when tacit know-how is more important, and that common ownership improves post-transfer outcomes conditional on adoption. I test these predictions using U.S. patent reassignments between publicly traded firms. Using within-deal variation across competing potential adopters and plausibly exogenous variation from passive index-fund holdings, I show that common ownership increases the likelihood that a firm acquires a technology, particularly when the transferred bundle is more tacit. Common ownership predicts stronger subsequent innovation and higher future firm value, especially when ownership overlap is concentrated among investors with stronger incentives to monitor the provider. These findings show how ownership structure shapes interfirm technology transfer by affecting not only who acquires a technology, but also how much value is created.
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Geopolitical Tensions And Multinational Brands: Evidence From China
Rongyu Cui, Xiang Li
Finance Research Letters,
Vol. 85 (November),
2025
Abstract
Using brand-level sales data from Chinese e-commerce platforms, this study examines how geopolitical tensions affect multinational brands operating in China. Merging these sales data with a U.S.–China tension index, we use panel regressions and local projections to show that rising tensions significantly reduce the market share of U.S. brands in China relative to brands from other countries, with the effects persisting for up to 12 months. An event study employing a difference-in-differences framework, centered on brand-specific incidents of political tension with China, reveals similar market share declines among affected brands, highlighting consumer sentiment as a key transmission channel.
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Real Estate Transaction Taxes and Credit Supply
Michael Koetter, Philipp Marek, Antonios Mavropoulos
Journal of Financial Stability,
Vol. 80 (September),
2025
Abstract
We exploit staggered real estate transaction tax (RETT) hikes across German states to identify the effect of house price changes on mortgage credit supply. Based on approximately 33 million real estate online listings, we construct a quarterly hedonic house price index (HPI) between 2008:q1 and 2017:q4, which we instrument with state-specific RETT changes to isolate the effect on mortgage credit supply by all local German banks. First, a RETT hike by one percentage point reduces HPI by 1.2%. This effect is driven by listings in rural regions. Second, a 1% contraction of HPI induced by an increase in the RETT leads to a 1.4% decline in mortgage lending. This transmission of fiscal policy to mortgage credit supply is effective across almost the entire bank capitalization distribution.
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Research Data Centre
Research Data Centre (IWH-RDC) Direct link to our Data Offer The IWH Research Data Centre offers external researchers access to microdata and micro-aggregated data sets that…
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Research Articles
Research Articles Explore cutting-edge research based on CompNet’s micro-aggregated firm-level data and related analytical tools. These articles cover empirical and theoretical…
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European Real Estate Index (EREI) 2025
Michael Koetter, Felix Noth, Fabian Woebbeking
IWH Technical Reports,
No. 1,
2025
Abstract
This Technical Report documents the construction and coverage of the IWH European Real Estate Index (EREI). Since 2018, we have used machine-learning methods to collect monthly listings of residential real estate available for sale or rent in up to 20 European countries. The Technical Report documents the cleaning and selection process and describes the data regarding coverage, moments, and frequencies to construct the EREI.
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Essays on Firms and Market Performance
Tommaso Bighelli
PhD Thesis, db-thueringen,
2024
Abstract
In Chapter 1, I combine longitudinal administrative firm-level data from Germany with 8,000 local tax changes for identification to show that local tax hikes (cuts) increase (decrease) the local manufacturing share. Firm-level results reveal that this is due to wage, employment, firm entry, and labor productivity in the service sector being more responsive to a tax shock than in manufacturing. With this evidence in mind, I calibrate a two-sector model with heterogeneous firms and profit tax to show that, owing to different structural parameters, a corporate tax cut disproportionately benefits service firms, contributing to the sectoral reallocation from manufacturing to service. In Chapter 2, we derive a European Herfindahl-Hirschman concentration index from 15 micro-aggregated country datasets. We show that European concentration rose due to a reallocation of economic activity towards large and concentrated industries. Over the same period, productivity gains from an increasing allocative efficiency of the European market accounted for 50% of European productivity growth while markups stayed constant. Using country-industry variation, we show that changes in concentration are positively associated with changes in productivity and allocative efficiency. This holds across most sectors and countries and supports the notion that rising concentration in Europe reflects a more efficient market environment rather than weak competition and rising market power. In chapter 3, We study the consequences of the Covid-19 pandemic and related policy support on productivity. We employ an extensive micro-distributed exercise to access otherwise unavailable individual data on firm performance and government subsidies. Our cross-country evidence for five EU countries shows that the pandemic led to a significant short-term decline in aggregate productivity and the direct support to firms had only a limited positive effect on productivity developments.
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East Germany
The Nasty Gap 30 years after unification: Why East Germany is still 20% poorer than the West Dossier In a nutshell The East German economic convergence process is hardly…
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A Multi-Model Assessment of Inequality and Climate Change
Marie Young-Brun, et al.
Nature Climate Change,
Vol. 14 (12),
2024
Abstract
Climate change and inequality are critical and interrelated issues. Despite growing empirical evidence on the distributional implications of climate policies and climate risks, mainstream model-based assessments are often silent on the interplay between climate change and economic inequality. Here we fill this gap through an ensemble of eight large-scale integrated assessment models that belong to different economic paradigms and feature income heterogeneity. We quantify the distributional implications of climate impacts and of the varying compensation schemes of climate policies compatible with the goals of the Paris Agreement. By 2100, climate impacts will increase inequality by 1.4 points of the Gini index on average. Maintaining global mean temperature below 1.5 °C reduces long-term inequality increase by two-thirds but increases it slightly in the short term. However, equal per-capita redistribution can offset the short-term effect, lowering the Gini index by almost two points. We quantify model uncertainty and find robust evidence that well-designed policies can help stabilize climate and promote economic inclusion.
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