Bank–firms topology in Italy

An empirical analysis of the Italian system of banks and firms is carried out using the network theory. The emerging architecture of this economic network shows peculiar behaviors: (i) Multiple lending is very widespread; (ii) Small firms are preferentially financed by small banks; (iii) Large firms are financed by many banks; (iv) the ratio between loans and deposits is much higher for large banks than for small banks, while (v) strong size heterogeneity appears among co-financing banks, and (vi) the spanning-tree is very hierarchical.