The DOJ and FTC clarify the role of labor market power ("monopsony") in the 2023 draft merger guidelines. The draft … that a stricter threshold may be warranted in labor markets. The post-merger Herfindahl-Hirschman Index (HHI) that defines … monopsony power in the U.S. may warrant an even lower threshold. For example, merger simulations indicate that workers would …

aggregate variety increases following a merger. However, with fixed cost synergies, an increase in aggregate variety can … indicate that the merger is beneficial. Our results also show high synergies do not necessarily improve consumer welfare. …