Bond Maintenance Requirement and Sovereign Yields

This paper revisits the notion of a regulatory premium on certain assets. Central banks impose specific requirements on the types of bonds eligible for holding as collateral for monetary policy operations or lending facilities. In line with the predictions of the preferred-habitat view, meeting the policy requirements can result in certain bonds holding a premium compared to similar bonds that fail to meet the eligibility criteria.

The Central Bank of Türkiye introduced a new monetary policy framework requiring Turkish banks to maintain long-term fixed rate domestic currency denominated sovereign bonds in blocked accounts against specific conditions. In this paper, we analyze how the so-called bond maintenance requirement affects the pricing in the bond market. Our findings indicate that the policy resulted in a significant decline in yields for eligible bonds, and it has varying effects along the sovereign bond yield curve. We document that if there had been no policy introduction, the long end of the sovereign bond yield curve would have been much steeper. Then, we observe that the eligibility discount has a temporary nature, and the yield for an eligible bond increases immediately when it switches to a non-eligible status. Next, we show that there is a non-linear relationship between eligibility discount and time-to-maturity for an eligible bond. Initially, the discount increases as the time-to-maturity lengthens, reaching a peak level. Beyond this point, it starts to decline for bonds in the longest time-to-maturity category. Finally, we provide preliminary findings that the policy has significant spillovers in financial markets: causing an increase in interest rate hedging costs, a rise in deposit rates and segmentation in bond pricing.