In the shadow of the interlocking directorates regulation. A comparative case study

- Network analysis techniques are used for investigating the probable effects of a change in the regulation that aims to prevent the anticompetitive effects of the crossed presence of the same administrators in the boards of directors of competing firms, known as interlocking directorates (ID). The case study considered is a recent Italian law (Section 36 of Law Decree n. 201/2011) which prohibits ID on the boards of credit, insurance and financial companies. The ID networks of the top-100 Italian listed companies and of the financial companies in this same list are considered and compared with the analogous networks in the U.S.. The U.S. networks represent a benchmark given that in the U.S. companies act in the shadow of the Section 8 of the Clayton Act that has banned ID since 1914. The effects on the ID networks of the new Italian law are simulated under two different interpretations of the law. If the law will be applied according to a narrow interpretation, Italian ID network will rest substantially unaltered. On the other hand if the law will be applied according to a broad interpretation, the ID network for financial firms will be completely modified with a network configuration very similar to the American benchmark.