Mahmoud Fatouh and Ioana Neamțu
Similar to the Deutsche Bank’s episode in 2016 and the Covid stress in 2020, AT1 spreads over subordinated debt rose rapidly and sharply following the Credit Swiss rescue deal. Beyond these three cases, AT1 spreads have been stable. In this post, we focus on conversion risk of AT1 bonds (also known as contingent convertible, CoCo, bonds) to explain the sharp rise in AT1 spreads in these three cases. Conversion risk is the main additional risk of AT1 bonds, compared to subordinated debt. It arises from the potential wealth transfer from AT1 bondholders to existing shareholders when AT1 conversion is triggered, conditional on the solvency of the issuer. We show that, in normal times, investors believe conversion risk is very low, but major events can change this significantly, largely due to higher uncertainty.
