Gender quotas, board diversity and spillover effects. Evidence from Italian banks

We study the impact of a 2011 law on the diversity of bank boards. The law required all listed companies in Italy (including banks) to increase the share of female representatives on their boards up to one third of total seats. We look at listed banks (the ones directly targeted by the law), but also test whether the law led to spillover effects on non-listed banks belonging to listed groups. Using administrative data on board composition between 2007 and 2019, we compare some measures of diversity of boards of listed and unlisted banks belonging to listed groups with those of institutions included in non-listed groups, before and after the introduction of the law. We find that female representation increased only for listed banks, with no spillover effects of the law on those belonging to listed groups, while the economic performance of listed banks remained broadly unchanged.