United States v. Philadelphia National Bank

Application of federal antitrust law to bank mergers and market-concentration analysis.

The United States challenged the proposed merger of Philadelphia National Bank and Girard Trust Corn Exchange Bank, arguing that the combination would substantially lessen competition in commercial banking in the Philadelphia metropolitan area.

The Court held that Section 7 of the Clayton Act applied to bank mergers and that the proposed merger was unlawful because of its likely anticompetitive effects.

The Court treated banking as a commercial market subject to antitrust constraints despite the presence of specialized banking regulators. It emphasized market definition, concentration, entry conditions, and Congress's judgment that economic concentration can be harmful even when a merger might produce administrative or business efficiencies.

1. How does the allocation of regulatory authority affect coordination, expertise, and capture risk?
2. Which private or systemic risks remain outside the court’s doctrinal inquiry?