There have been many proposals about the appropriate design of contingent capital since 2008 from the academic community. Some of them are described below to illustrate the variety, complexity, and the ongoing development of contingent capital market.
Squam Lake Working Group (2009) suggested a conversion from debt to equity if two conditions are met. The first condition is an industry-level event such as a declaration by regulators that the financial system is suffering from a systemic crisis. The second is an institution-based event such as a violation of covenants in the hybrid-security contract. A promising candidate of the covenant is the capital adequacy ratio (Bank's Tier 1 Capital/risk adjusted assets).
McDonald (2011) analyzed a dual trigger design based on the firm's stock price and the value of a financial institutions index. This structure potentially protects financial firms during a crisis, when all are performing badly, but during normal times it allows a bank with bad performance to go bankrupt.
Kashyap et al. (2008) proposed using capital insurance that would "transfer more capital onto the balance sheets of banking firms in those states when aggregate bank capital is, from a social point of view, particularly scarce."26
Flannery (2009) proposed “Contingent capital certificates” (CCC) that "would be issued as debt obligations, but would convert into common stock if the issuer’s capital ratio fell below some critical, pre-specified value." It is suggested to be applied to systemically important firms. However, the condition of conversion and its specification are complicated compared to other proposals. Flanery’s key features are quoted It is an insurance contract, not like a contingent convertible bond. The trigger of insurance payoff is based on the capital loss of the total banking industry. The insurance payment can help.