While the Dodd Frank Act (DFA) broadens the regulatory reach to reduce systemic risks to the U.S. financial system, it does not address some important risks that could migrate to or emanate from entities outside the federal safety net. At the same time, it limits the types of interventions by...

The concentration of risk within financial system is considered to be a source of systemic instability. We propose a theory to explain the structure of the financial system and show how it alters the risk taking incentives of financial institutions. We build a model of portfolio choice and...