Abstract This paper studies how the labor market frictions of skilled workers affect corporate valuation. The analysis features immigrant workers’ mobility constraints imposed by the U.S. green card application process and exploits exogenous variations caused by imperfections in the current immigration system. The study finds that relaxing mobility constraints negatively influences firm value. This effect is stronger for firms with higher labor adjustment costs. Reductions in investments and increases in labor costs are channels through which labor mobility adversely affects firm value. The findings suggest that monopoly rent over skilled workers is an important economic determinant of corporate valuation.

ABSTRACT Mergers of firms that share labor markets increase labor market concentration which can lead to labor efficiency gains and/or create labor market power for the merged firms. Using a novel measure based on establishment‐level employment data, we find that merger‐induced increases in labor market concentration explain value creation in a sample of completed U.S. public firm mergers from 1991 to 2016. Analysis of the stock market reactions of rival, supplier, and customer firms, as well as firm‐ and establishment‐level real effects in the merging firms, supports a labor efficiency explanation of these merger gains.