We provide the first estimates of the extent of common ownership of competing firms in Australia. Combining data on market shares and substantial shareholdings, we calculate the impact of common ownership on effective market concentration. Among firms where we can identify at least one owner, 31...

We evaluate the impact of the Washington State Attorney General's enforcement campaign against employee no-poaching clauses in franchising contracts, which unfolded from 2018 through early 2020. Implementing a staggered difference-in-differences research design using Burning Glass Technologies...

We introduce a simple oligopolistic trade model with international transportation costs, and analyze the profitability and the social desirability of national vs. international mergers in relation to three different issues, (i) the level of trade freeness, (ii) the possibility of rent...

We study the restructuring of the labor force after mergers and acquisitions. Overall restructuring is large. Net employment of targets declines by more than half within two years after acquisitions relative to a matched sample, and is concentrated in targets that close all establishments. There...

Evidence suggests that hospital mergers can reduce costs but less is known about their effects on patient outcomes. We study how a wave of mergers that led to the shutdown of one third of all Swedish maternity wards affected the health of mothers who gave birth and their newborns. Applying a...

How does employer market power affect workers? We compute the concentration of new hires by occupation and commuting zone in France using linked employer-employee data. Using instrumental variables with worker and firm fixed effects, we find that a 10% increase in labor market concentration...

The merger of populations expands the comparison space of incomes. As a result, measures of the income-based social stress and of the income inequality of the constituent populations need to be replaced by new measures. To this end, we develop a procedure for calculating the aggregate social...

The DOJ and FTC clarify the role of labor market power ("monopsony") in the 2023 draft merger guidelines. The draft states in Guideline 11 that the structural presumption threshold applies to labor market concentration, while also suggesting that a stricter threshold may be warranted in labor...