Antitrust Law and Business Dynamism

In this paper, I study firms' strategic and anticompetitive behaviour, and the consequent role of antitrust law as a macroeconomic policy in promoting business dynamism. Over the past few decades, business dynamism has been declining in the US: firm entry has fallen, accompanied by a slowdown in the rate of productivity growth. Additionally, enforcement of antitrust law has been at historically low levels. Using firm-level and sector-level data from the US, I find that stronger antitrust enforcement is associated with higher entry and higher productivity growth but lower R&D investments. Next, I develop and structurally estimate a dynamic general equilibrium model with innovation and oligopolistic product market competition. The dynamic structure of the model allows rms to eliminate competition through strategic decision making. The model is calibrated to the recent US experience and quantitative exercises show that strengthening antitrust policies results in: (1) a higher firm entry rate, (2) a higher rate of productivity growth, (3) a larger labour share of GDP, and (4) a decline in the innovation rate. Overall, the model indicates that stronger antitrust policies are effective at restoring business dynamism and can deliver up to 16% higher welfare in consumption-equivalent terms. The improvement in welfare is mainly driven by an increase in the welfare of workers, without affecting the capitalists, suggesting that antitrust law has distributional implications, and therefore, has a potential role in reducing inequality.