Article 259(2) CRR allows an institution to infer an external rating of a reference position to an unrated IRBA securitisation position if the following requirements are met: 1. the reference position is subordinate in all respects to the unrated securitisation position 2. the maturity of the reference position is equal to or longer than that of the unrated position 3. any inferred rating is updated on an ongoing basis to reflect any changes in the credit assessment of the reference position. According to Article 245(3) CRR, securitisation positions must include exposures to a securitisation arising from interest rate or currency derivative contracts, the so called ‘market value hedging transactions’. The CRR does not contain any specific rules for determining the IRBA risk weight of those exposures, but does acknowledge that market value hedging transactions warrant a specific treatment, e.g. 1. Article 255(1)(d) CRR allows for applying a 50% CCF for unrated liquidity facilities if the repayment is not subordinated to any claims other than to claims arising in respect of market value hedging transactions 2. Article 261(1) CRR allows for classifying a securitisation tranche as most senior although market value hedging transactions exist that are more senior.