Board gender diversity and performance in family firms: exploring the faultline of family ties

Using a sample of 1134 firm-year observations of non-financial family firms listed on the Spanish stock market in the period 2003–2020, we explore how women directors affect company performance, distinguishing between family and non-family female members on the board. We believe there might be faultlines between family and non-family women on boards that may well impair performance due to differences in agency conflicts and socioemotional links with the family firm. As the number of female family directors grows, we reveal that conflicts with non-family sub-groups become more prevalent, impairing firm performance. Opening boards to non-family women does, however, seem to be an effective way of enhancing firm performance when there is a critical mass of female directors. The results are robust to alternative measures of board gender diversity and different econometric specifications.