Contingent convertible bonds, or CoCos, are debt instruments that automatically convert to equity or absorb losses when a bank's capital falls below a predefined trigger. Proponents argue they strengthen loss-absorbing capacity and reduce the need for taxpayer-funded rescues; critics warn that poorly designed triggers and market reactions can increase fragility during downturns. Nicolas Véron Bruegel has examined how design choices shape these trade-offs, emphasizing that legal enforceability and clear trigger mechanics matter for credibility.
Loss absorption versus trigger risk
In theory, loss absorption supplied by CoCos raises a bank’s ability to withstand shocks and thus lowers systemic risk by internalizing losses. The Basel Committee on Banking Supervision Bank for International Settlements has incorporated principles for loss-absorbing capacity into regulatory frameworks, stressing that contingent capital can complement equity and resolution tools. However, conversion triggers can be a double-edged sword. If triggers are market-based or poorly communicated, they may induce pre-emptive asset sales, margin calls, or runs as investors anticipate dilution. That behavior can amplify stress across institutions holding similar instruments.
Contagion channels and real-world frictions
Conversion events can transmit shocks through several channels. First, sudden dilution or forced equity issuance can undermine a failing bank’s counterparty relationships, increasing funding costs. Second, investors holding CoCos across multiple banks may be simultaneously hit, creating correlated losses and mutual fire sales in secondary markets. Third, legal and territorial differences complicate cross-border resolution; creditor hierarchy and bail-in powers vary across jurisdictions, affecting the predictability of outcomes and investor confidence. Cultural attitudes toward bail-ins and political tolerance for bank losses also shape how stakeholders react during crises.
Empirical and policy reviews stress that outcomes depend heavily on instrument design, supervisory capacity, and market structure. Nicolas Véron Bruegel highlights that transparent, accounting-based triggers combined with pre-specified conversion mechanics reduce uncertainty. The Basel Committee on Banking Supervision Bank for International Settlements underscores coordination with resolution regimes such as TLAC and bail-in frameworks to avoid cliff effects. In practice, properly calibrated CoCos can reduce reliance on public backstops and improve resilience, but mis-specified instruments risk creating procyclical feedbacks that increase, rather than diminish, systemic risk during downturns. Careful regulatory design and cross-border legal alignment are therefore essential to realize benefits without unintended contagion.