This paper provides empirical evidence consistent with the facts that (1) social networks may strongly affect board composition and (2) social networks may be detrimental to corporate governance. Our empirical investigation relies on a large dataset on executives and outside directors of corporations listed on the Paris stock exchange over the 1992-2003 period. This data source is a matched employer employee dataset providing both detailed information on directors/CEOs and information on the firm employing them. We first find a very strong and robust correlation between the CEO's network and that of his directors. Networks of former high ranking civil servants are the most active in shaping board composition. Our identification strategy takes into account (1) firm and directors' fixed effects and (2) matching of firms and director along one observable and one unobservable characteristic. We then turn to real effects of such network activity. We find that firms where these networks are most active are less likely to change CEO when they underperform. This suggests that social networks in the board room impair corporate governance.
