Does higher labor market concentration lower wages for new hires?
Core argument: A 10% rise in labor market concentration is associated with a 0.9% decline in wages for new hires in France, consistent with monopsony theory, according to instrumental variable estimates using French administrative data with worker and firm fixed effects.
Evidence from France indicates that a 10% rise in labor market concentration results in a 0.9% decrease in wages for new hires, aligning with Monopsony Theory. This relationship is supported by data showing a negative correlation between labor market concentration and both wages and recruitment flows. The study uses French administrative data and instrumental variable estimates with worker and firm fixed effects to demonstrate these effects, noting that the impact is less severe in more unionized industries. Conversely, a 10% increase in product market concentration can lead to a 0.9% wage increase, suggesting rent-sharing benefits, although its effect on hiring is less consistent.

















Ed Comment:“…how on earth can someone in the us monopolize a region labor market. It would have to be a big factory (or hospital) in rural America—something rural America would be rejoicing to have. Otherwise it’s a city or the country side with a couple of gas stations….”
Implication for anti-trust work, “…We find that a horizontal merger has an impact not only on workers in the affected industry, but also on workers in other industries that share the same occupation:for a merger between the top two employers in the retail industry, about 25% of the impacts affect workers outside the retail industry. Compared to mergers in other industries, a merger between the top two employers in the retail industry would be the most damaging overall, with about 24 million annual decrease in the wages of new hires, and about an 8000 decrease in annual hires. Our comprehensive data allows us to show that employer market power has a substantial effect on labor market outcomes even in countries like France where union coverage is high and labor market institutions are protective of workers. Our findings suggest that antitrust and competition authorities should further scrutinize the effects of competition policy on workers….”