Jon Peace, a banking analyst at Nomura, counts at least 25 large publicly traded banks that would need more capital if they fully recognized losses in the value of their holdings of European government bonds. The list includes big names like Commerzbank and Deutsche Bank in Germany, UniCredit in Italy, and Société Générale and BNP Paribas in France.

In addition, there may be dozens, if not hundreds, of other undercapitalized banks that fall below the radar of analysts because they do not have publicly traded shares, like German landesbanks, or because they are too small.