There is a pressure for convergence in the area of merger control in the EU member states. How is this pressure spelled out in German, British, and French merger control? Do the three countries’ merger control regimes have recognizable ideational foundations and policies? Through a careful, detailed comparison we reveal significant differences and similarities between the three countries. A clear relationship can be traced between each country’s merger control setup and an ism on the state – market relationship: German ordoliberalism, Britishneoliberalism, and French mercantilism. Pressures for European convergence coexist with significant traces of ideational national foundations.