Nonbank financial intermediaries (NBFIs) have grown significantly relative to banks. We argue that this growth reflects a transformation of the activities and risks of banks and NBFIs, driven at least in part by changes in bank regulation. We document through new regulatory data, case studies, and empirical analyses that banks remain special as providers of both routine and emergency liquidity to NBFIs and that the sectors have become increasingly interdependent. We discuss some potential regulatory responses, including considering the two sectors holistically and exploring new ways to internalize the costs of systemic risk arising from bank-NBFI interconnectedness.

Systemic risk is modeled as the endogenously chosen correlation of returns on assets held by banks. The limited liability of banks and the presence of a negative externality of one bank’s failure on the health of other banks give rise to a systemic risk-shifting incentive where all banks undertake correlated investments, thereby increasing economy-wide aggregate risk. Regulatory mechanisms such as bank closure policy and capital adequacy requirements that are commonly based only on a bank’s own risk fail to mitigate aggregate risk-shifting incentives, and can, in fact, accentuate systemic risk. Prudential regulation is shown to operate at a collective level, regulating each bank as a function of both its joint (correlated) risk with other banks as well as its individual (bank-specific) risk.

While the too-big-to-fail guarantee is explicitly a part of bank regulation in many countries, this paper shows that bank closure policies also suffer from an implicit “too-many-to-fail” problem: when the number of bank failures is large, the regulator finds it ex-post optimal to bail out some or all failed banks, whereas when the number of bank failures is small, failed banks can be acquired by the surviving banks. This gives banks incentives to herd and increases the risk that many banks may fail together. The ex-post optimal regulation may thus be time-inconsistent or sub-optimal from an ex-ante standpoint. In contrast to the too-big-to-fail problem which mainly affects large banks, we show that the too-many-to-fail problem affects small banks more by giving them stronger incentives to herd.

The merit of international convergence of bank capital requirements in the presence of divergent closure policies of different central banks is examined. The lack of a complementary variation between minimum bank capital requirements and regulatory forbearance leads to a spillover from more forbearing to less forbearing economies and reduces the competitive advantage of banks in less forbearing economies. Linking the central bank's forbearance to its alignment with domestic bank owners, it is shown that in equilibrium, a regression toward the worst closure policy may result: The central banks of initially less forbearing economies also adopt greater forbearance.

We show that eurozone bank risks during 2007–2013 can be understood as carry trade behavior. Bank equity returns load positively on peripheral (Greece, Italy, Ireland, Portugal, Spain, or GIIPS) bond returns and negatively on German government bond returns, which generated carry until the deteriorating GIIPS bond returns adversely affected bank balance sheets. We find support for risk-shifting and regulatory arbitrage motives at banks in that carry trade behavior is stronger for large banks and banks with low capital ratios and high risk-weighted assets. We also find evidence for home bias and moral suasion in the subsample of GIIPS banks.

Regulation Conference at the Bank of Portugal, and two anonymous referees for useful comments. All errors remain our own.

This paper analyzes corporate bond valuation and optimal call and default rules when interest rates and firm value are stochastic. It then uses the results to explain the dynamics of hedging. Bankruptcy rules are important determinants of corporate bond sensitivity to interest rates and firm value. Although endogenous and exogenous bankruptcy models can be calibrated to produce the same prices, they can have very different hedging implications. We show that empirical results on the relation between corporate spreads and Treasury rates provide evidence on duration, and we find that the endogenous model explains the empirical patterns better than do typical exogenous models.

Can banks maintain their advantage as liquidity providers when exposed to a financial crisis? While banks honored credit lines drawn by firms during the 2007 to 2009 crisis, this liquidity provision was only possible because of explicit, large support from the government and government‐sponsored agencies. At the onset of the crisis, aggregate deposit inflows into banks weakened and their loan‐to‐deposit shortfalls widened. These patterns were pronounced at banks with greater undrawn commitments. Such banks sought to attract deposits by offering higher rates, but the resulting private funding was insufficient to cover shortfalls and they reduced new credit.

Low monetary policy rates lower the cost of capital for firms, thereby spurring productive investment. Low interest rates however can also induce the private sector to enter into risky carry trades when they imply that the earned carry more than offsets liquidity risk. Such carry trades and productive investment compete for funds, so much so that the former may crowd out the latter. Below an endogenous lower bound, monetary easing generates only limited capital expenditures that come at the cost of large and destabilizing financial risk-taking. Absent the ability to regulate carry trades, monetary easing must be complemented with a restrictive emergency-lending policy in the form of higher lending rates so as to discourage risk-taking by relatively illiquid firms. Monetary easing, tepid investment response, and rollover risk for liquid firms then arise jointly (and optimally) in equilibrium.