Before revision: This paper considers a top-down approach for CDO valuation and proposes a market model. We extend previous research on this topic in two directions: on the one side, we use as driving process for the interest rate dynamics a time-inhomogeneous L\'evy process, and on the other side, we do not assume that all maturities are available in the market.
After revision: This paper considers a top-down setting driven by time-inhomogeneous L\'evy process, and on the other side, we do not assume that all maturities are available in the market.