As a result, mortgage brokers maximize their income by generating larger volumes of mortgages, as do the banks that package these loans into mortgage-backed securities (MBS’s). Investment banks then earn fees for re-packaging these securities in tranches of collateralized debt obligations, or CDO’s (and sometimes into CDO’s of CDO’s).
事实上，有许多金融中介现在可以在不承担信用风险的情况下赚取费率。其结果是，抵押贷款经纪人通过达成更大量的抵押贷款来使他们的收入最大化，而银行把这些贷款打包成抵押支持证券。投资银行然后再把这些证券打包成债务抵押债券（有时是债务抵押债券的债务抵押债券）来赚取费率。