2024-06-26
The Reserve Bank of New Zealand issued BPR132 to specify the types of credit risk mitigation recognized when banks calculate risk-weighted assets. The document mandates methodologies for recognizing collateral, on-balance sheet netting, guarantees, and credit derivatives under both standardized and internal ratings-based approaches. It establishes strict legal and operational conditions for mitigation recognition, including eligibility criteria for collateral and requirements to adjust for currency, asset, and maturity mismatches.
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BPR132 Credit Risk Mitigation Purpose of document This document specifies the types of credit risk mitigation that may be recognised when a bank calculates the risk-weighted asset (RWA) for a credit exposure, the conditions under which recognition is allowed, and the way that the recognised mitigation affects the RWA calculation. Banking Prudential Requirements July 2024
BPR132 1 Document version history 1 July 2021 First issue date 1 October 2021 Minor formatting improvements 1 October 2023 Updated for technical changes 1 July 2024 Revised for minor correction Conditions of registration The Banking (Prudential Supervision) Act 1989 (the Act) permits the Reserve Bank to impose conditions of registration (conditions) on registered banks1 . This document BPR132: Credit Risk Mitigation forms part of the requirements for the following conditions:* A New Zealand-incorporated registered bank is normally subject to a condition requiring it to maintain capital ratios above specified minimum levels, and also to a condition imposing restrictions on its dividend payments when its prudential capital buffer ratio falls below specified levels2 . This document sets out the methodology for recognising credit risk mitigation in the calculation of credit risk RWAs. A New Zealand-incorporated registered bank needs to calculate total credit risk RWAs as part of calculating its day-to-day values for the capital ratios and the capital buffer ratio, and hence monitor its compliance with these capital adequacy conditions.
1 The conditions can relate to any of the matters referred to in sections 73 to 73B, 78, and 81 of the Act. The standard conditions are contained in Appendix 1 of document BS1: Statement of Principles. 2 These conditions of registration relate to the matter referred to in: section 78(1)(c) of the Act (capital in relation to the size and nature of the business).
BPR132 2 BPR132: Credit Risk Mitigation Part A: Introduction Part B: Collateral Part C: On-balance sheet netting Part D: Treatment of guarantees and credit derivatives under standardised and IRB approaches Part E: Maturity mismatch Contents Part A: Introduction A1 Purpose and applications A1.1 Purpose A1.2 Application A2 General requirements for recognition of credit risk mitigation A2.1 Recognition of credit risk mitigation: standardised approach A2.2 Recognition of credit risk mitigation: IRB approach A2.3 General conditions on recognition of credit risk mitigants Part B: Collateral B1 Methodology and general requirements B1.1 Simple and comprehensive approaches B1.2 Eligible collateral B1.3 Minimum requirements for collateral B2 Treatment of collateral: comprehensive approach B2.1 Use of collateral B2.2 Calculation of adjusted exposure amount for collateralised transactions B2.3 Standard supervisory haircuts B2.4 Adjustments to standard supervisory haircuts where standard assumptions do not apply B2.5 Adjustment for haircuts B2.6 Conditions for a zero haircut B2.7 Core market participants B2.8 Recognition of SFTs covered by master netting agreements B2.9 Formula for calculating exposure under master netting agreement B3 Treatment of collateral: simple approach B3.1 Recognition of collateral B3.2 Risk weighting of collateralised transaction Part C: On-balance sheet netting C1 Recognition of on-balance sheet netting C1.1 On-balance sheet netting of loans and deposits C1.2 Requirements for on-balance sheet netting C2 Calculation of exposure value C2.1 Treatment of loans and deposits C2.2 Formula for calculating exposure Part D: Treatment of guarantees and credit derivatives under standardised and IRB approaches D1 Treatment of guarantees and credit derivatives under standardised approach D1.1 Introduction and application D1.2 Conditions applying to recognition of guarantees and credit derivatives for RWA calculation D1.3 Additional eligibility requirements for guarantees D1.4 Eligible types of credit derivative D1.5 Credit events to be covered under terms of credit derivative
BPR132 3 D1.6 Cash-settled credit derivatives D1.7 Asset mismatch in relation to credit derivative D1.8 Treatment of cash-funded creditlinked notes D1.9 Currency mismatch adjustment D1.10 Maturity mismatch adjustment D1.11 Method of recognition in RWA calculation D2 Treatment of guarantees and credit derivatives under IRB approach D2.1 Use of guarantees and credit derivatives under IRB approach D2.2 Conditions applying to recognition of guarantees and credit derivatives for IRB RWA calculation D2.3 Guarantees and credit derivatives: reflection in PD or LGD estimates D2.4 Ratings of obligor and credit protection provider D2.5 Guarantees and credit derivatives: retention of information D2.6 Guarantees and credit derivatives: limits on adjustments of PD or LGD D2.7 Criteria for adjusting PD/LGD D2.8 Criteria for adjusting PD/LGD: further requirements applying to credit derivatives D2.9 Effect of adjustments on EL calculation Part E: Maturity mismatch E1 Meaning and adjustments E1.1 Meaning of maturity mismatch E1.2 Effective residual maturity E1.3 Limitations on recognition of credit risk mitigants with maturity mismatch E1.4 Maturity mismatch adjustment
BPR132 4 Part A: Introduction A1 Purpose and applications A1.1 Purpose This document sets out the calculation methods a bank must use, and the conditions that must be met, for recognising the benefits of credit risk mitigation when calculating credit risk RWAs. A1.2 Application
BPR132 5 6. The different approaches available for the different cases of credit risk mitigation are summarised in Table A1.2. Table A1.2: Guidance on general application of credit risk mitigation Collateral posted by a counterparty or by a third party on behalf of the counterparty IRB exposure (only applies to any part of EAD arising from counterparty credit risk) Standardised exposure For counterparty exposures in the banking book The bank must use the comprehensive approach. The bank may use either the comprehensive approach or the simple approach. For counterparty exposures in the trading book The bank must use the comprehensive approach. The bank must use the comprehensive approach. Under the comprehensive approach, the bank reduces the exposure amount to the counterparty by a prescribed amount of the collateral posted. Under the simple approach, the bank risk-weights the collateralised portion of the counterparty exposure by the risk-weight that applies to the collateral as an exposure On balance-sheet netting IRB exposure Standardised exposure In calculating EAD, the bank may net the exposure amount against a deposit held, subject to relevant requirements and mismatch adjustments. The bank may net the exposure against a deposit held, subject to relevant requirements and mismatch adjustments. Guarantees and credit derivatives IRB exposure Standardised exposure The bank must adjust the PD and/or LGD inputs used to model RWA for the exposure. The bank must use the substitution approach. Under the substitution approach the bank applies the risk-weight of the provider (guarantor or credit derivative seller) instead of the underlying exposure of the obligor. A2 General requirements for recognition of credit risk mitigation A2.1 Recognition of credit risk mitigation: standardised approach A bank using the standardised approach to calculate the RWA for a credit risk exposure may recognise credit risk mitigation on that exposure only if– a. the credit risk mitigation is of one of the types covered in this document and meets all requirements in this document applicable to that type of credit risk mitigation, apart from the requirements in Subpart D2; and Guidance: Subpart D2 is only applicable to recognition of guarantees and credit derivatives under the IRB approach. b. in calculating the RWA, the bank uses the calculation method specified in this document to take account of the credit risk mitigation.
BPR132 6 A2.2 Recognition of credit risk mitigation: IRB approach
BPR132 7 A2.3 General conditions on recognition of credit risk mitigants
BPR132 8 Part B: Collateral B1 Methodology and general requirements B1.1 Simple and comprehensive approaches
BPR132 9 B1.2 Eligible collateral
BPR132 10 a. there must be a formal written contractual agreement between the bank and the counterparty or third party lodging the collateral which establishes the bank’s direct, explicit, irrevocable, and unconditional recourse to the collateral; and b. the legal mechanism by which collateral is pledged or transferred must ensure that the bank has the right to liquidate or take legal possession of it immediately in the event of the default, insolvency, statutory management, voluntary administration, receivership, or bankruptcy of the counterparty or custodian of the collateral, or where any other credit event occurs that is defined in the transaction documentation as permitting enforcement of collateral; and c. the bank must take all steps necessary to fulfil requirements under the law applicable to its interest in the collateral for obtaining and maintaining an enforceable security interest. Guidance: This includes clear and robust procedures for the immediate liquidation of collateral to ensure that any legal conditions required for declaring the default of the counterparty and liquidating the collateral are observed and that the collateral can be liquidated promptly. 3. The lodging requirements are that– a. cash collateral must be lodged with the bank; and b. cash collateral in the form of a certificate of deposit or bank bill issued by the bank must be retained by the bank (that is, the bank must have physical possession of it) until the collateral obligations have been extinguished; and c. collateral, other than cash collateral, must be held by either the bank, an independent custodian, or some other third party and, if it is not held by the bank, the bank must ensure that the actual holder segregates the collateral from the holder’s own assets; and d. in the case of collateral lodged on behalf of the counterparty by a third party, there must be collateral agreements in place with the third party that satisfy the requirements of subsection (2). 4. Under the comprehensive approach, collateral that is lodged for a shorter period than that of the underlying exposure may be recognised, but only if the requirements for maturity mismatch are satisfied (see Part E). B2 Treatment of collateral: comprehensive approach B2.1 Use of collateral
BPR132 11 b. in all other cases, the formula set out in section B2.2. 2. Using haircuts, the bank must adjust both the amount of the exposure to the counterparty (the volatility-adjusted exposure amount) and the value of the collateral (the volatility-adjusted collateral amount). 3. The size of the required haircuts depends on the type of instrument, the type of transaction, and the frequency of remargining or revaluing. 4. If the exposure and collateral are denominated in different currencies, the bank must make an additional downwards adjustment to the collateral amount to take into account possible future fluctuations in exchange rates. 5. For certain types of SFTs, a 0% haircut may be used to calculate the exposure amount after credit risk mitigation. Guidance: The conditions for a zero haircut are set out in section B2.6. 6. The adjusted exposure amount after credit risk mitigation, E*, is the difference between the volatility-adjusted exposure amount and the volatility-adjusted collateral amount. 7. Under the standardised approach, E* must be risk-weighted using the risk weight applicable to the underlying counterparty. 8. Under the IRB approach, E* forms part of the bank’s total net EAD for that counterparty. B2.2 Calculation of adjusted exposure amount for collateralised transactions
BPR132 12 2. When the exposure arises from the counterparty credit risk on a single derivative or bilaterally netted derivatives within the scope of Part E of BPR131, the bank must calculate the collateralised exposure amount using the following formula: E* = max{0, [CEA – C x(100% – HC – HFX)]} where— CEA is the credit equivalent amount of the derivative or netted derivatives calculated in accordance with Part E of BPR 131; and other terms have the meaning given in subsection (1). Guidance: This means that collateral held against a derivative or group of netted derivatives with a single counterparty is adjusted by the haircuts HC and HFX as applicable, with the haircuts adjusted in accordance with sections B2.4 and B2.5, but the haircut HE does not apply. If the collateral held against a derivative or group of netted derivatives is subject to a standard Credit Support Annex (or equivalent documentation), a currency mismatch arises on any of the collateral that is in a currency other than the Base Currency specified in the Credit Support Annex. Where a group of netted derivatives and the collateral held against them are in a mix of currencies, the bank may use any reasonable approach to determine which portions of the collateral can be matched by currency to portions of the net derivative exposure, and then apply the required haircut HFX to the rest of the collateral held. 3. For two or more SFTs with a given counterparty that are subject to a master netting agreement meeting the requirements of section B2.8, the adjusted exposure amount must be calculated using the formula in section B2.9. B2.3 Standard supervisory haircuts
BPR132 13 Table B2.3 – Standard supervisory haircuts (%) External rating grade for debt securities Residual maturity Sovereigns Other Issuers Securitisation exposures 1 (long- and short-term) ≤ 1 year 0.5 1 2
1 year, ≤ 5 years 2 4 8 5 years 4 8 16 2 or 3 (long- and short-term) and unrated bank securities ≤ 1 year 1 2 4 1 year, ≤ 5 years 3 6 12 5 years 6 12 24 4 (long-term) all 15 n/a n/a Equities in the NZX 50 or an overseas equivalent 15 Cash in the same currency 0 Currency mismatch (HFX) 8 Guidance: This table relates to the elements of the formula in section B2.2: HFX is the last item in the table (currency mismatch), the other items in the table being for the purposes of establishing HE and HC. The guidance note following section B2.5 explains how the necessary adjustments are to be made.
BPR132 14 B2.4 Adjustments to standard supervisory haircuts where standard assumptions do not apply
BPR132 15 Inserting those values into the formula would mean that the supervisory haircut (H) is 23.7%, calculated as follows: 𝐻 = 15% × √ 6+(20−1) 10 = 15% × √2.5 and hence H (haircut to use) = 23.7% (rounded). This value of H is inserted for the collateral haircut HC in the formula in section B2.2(1). B2.6 Conditions for a zero haircut For SFTs, where the counterparty is a core market participant (as defined in section B2.7), a haircut of zero will apply if the following conditions are satisfied: a. each of the exposure and the collateral is either cash, or a sovereign security qualifying for a 0% risk weight under section C2.2 of BPR131; and b. the exposure and the collateral are denominated in the same currency; and c. either the transaction is overnight or both the exposure and collateral are marked to market daily and are subject to daily remargining; and d. the collateral agreement specifies that, in the event of the counterparty’s failure to remargin, the time between the last mark to market before that event and the liquidation of the collateral is not more than 4 working days; and Guidance: This does not require the bank to always liquidate the collateral, but rather to have the capability to do so within the given time frame. e. the transaction is settled across a settlement system that is regularly used by core market participants for that type of transaction; and f. the documentation covering the agreement is standard ISDA documentation for SFTs in the securities concerned; and g. the transaction is governed by documentation specifying that, if the counterparty fails to satisfy an obligation to deliver cash or securities or to deliver a margin call or otherwise defaults, then the transaction is immediately terminable; and h. upon any default event, regardless of whether or not the counterparty is insolvent or bankrupt, the bank has an unequivocal, legally enforceable, right to immediately seize and liquidate the collateral for its own benefit. B2.7 Core market participants The following entities are considered core market participants: a. the New Zealand Government: b. the Reserve Bank of New Zealand: c. banks.
BPR132 16 B2.8 Recognition of SFTs covered by master netting agreements A bilateral netting agreement covering SFTs with a given counterparty is recognised as credit risk mitigation for RWA purposes if, in all relevant jurisdictions, it– a. is legally enforceable in the event of default, regardless of whether or not the counterparty is insolvent, bankrupt, or under statutory management; and b. gives the non-defaulting party the right to immediately terminate and close out all transactions under the agreement in the event of default, including in the event of insolvency, bankruptcy, or statutory management; and c. provides for the netting of gains and losses on transactions (including the value of any collateral) terminated and closed out under it so that a single net amount is owed by one party to the other; and d. allows for the immediate liquidation or set-off of collateral in the event of default, including in the event of insolvency, bankruptcy, or statutory management or other similar forms of administration. B2.9 Formula for calculating exposure under master netting agreement
BPR132 17 Sj is the net position in any security j (j = 1 to m), where individual positions in the security may arise either from lending the security (positive amount) or receiving the security as collateral (negative amount). Abs denotes the absolute value function Hj is the haircut applicable to security j, determined in accordance with sections B2.3 to B2.7. Sr fx is the net position in any security denominated in a currency different from the settlement currency (r = 1 to R), which is a subset of the full set of m securities (so that R ≤ m, and R may be zero). HFX is the foreign currency haircut applicable to security r, determined in accordance with sections B2.3 to B2.5. B3 Treatment of collateral: simple approach B3.1 Recognition of collateral
BPR132 18 ii. the collateral is in the form of sovereign securities eligible for a 0% risk weight, provided that the market value of the collateral used to determine the collateralised portion has been discounted by 20%; or b. an SFT that fulfils the conditions for a zero haircut set out in section B2.6 and is with a core market participant (as defined in section B2.7); or c. a derivative transaction in the banking book that is– i. marked to market on a daily basis; and ii. fully collateralised by cash; and iii. denominated in the same currency as the collateral: 3. A 10% risk weight may be applied to the portion of an exposure collateralised by eligible collateral if the transaction is– a. an SFT that fulfils the conditions for a zero haircut set out in section B2.6, but is not with a core market participant; or b. a derivative transaction collateralised by sovereign securities that qualify for a 0% risk weight. 4. For determining the portion of the claim to be treated as collateralised in this section, the bank must use the market value of the collateral at its most recent revaluation. Guidance: For example, a bank has a loan of $100 to a corporate borrower with a risk rating grade of 2. The bank holds collateral against the loan in the form of NZ government bonds with a current value of $60, under terms meeting the conditions in section B3.1. In this case, the bank may apply a 0% risk weight to $48 of the total exposure ($60 discounted by 20%, in accordance with subsection (2)(a)(ii)), and a 50% risk weight to the remaining $52 of the exposure (50% being the risk weight for a corporate with rating grade 2: see Table C2.7 of BPR131). The total RWA is then $26 (50% of $52).
BPR132 19 Part C: On-balance sheet netting C1 Recognition of on-balance sheet netting C1.1 On-balance sheet netting of loans and deposits This Part sets out the requirements for bilateral on-balance sheet netting of loans and deposits. C1.2 Requirements for on-balance sheet netting A bank may recognise on-balance sheet netting in calculating the RWA for a credit exposure when the following requirements are met: a. there must be a well-founded legal basis for concluding that the bilateral netting agreement is enforceable in each relevant jurisdiction, regardless of whether the counterparty is insolvent or bankrupt; and b. the bank must at all times be able to identify the loans and deposits that are subject to the bilateral netting agreement; and c. the bank must monitor and control its roll-off risks; and d. the bank must monitor and control the relevant exposure on a net basis. Guidance: Bilateral netting agreements with legal entities that are related to each other may be comingled, to the extent that the exposures and collateral can be rolled up into a single holding company or other unifying entity. C2 Calculation of exposure value C2.1 Treatment of loans and deposits
BPR132 20 E* is the exposure value after risk mitigation E is the current value of the exposure (that is, the value of the loans) to the counterparty subject to the bilateral netting agreement HFX is the supervisory haircut for a currency mismatch (specified as the last item in Table B2.3 in section B2.3(1)) adjusted, if revaluation takes place less frequently than daily (see section B2.4), in accordance with the formula in section B2.5 with the minimum holding period TM set at 10 days. CA is– i. the value of collateral (that is, the deposits), if there is no maturity mismatch between the deposits and the loans; or ii. if there is a maturity mismatch, the value determined in accordance with, and subject to the conditions in, Part E. 2. Under the standardised approach, the exposure value after recognising on-balance sheet netting is multiplied by the risk weight applicable to the counterparty. 3. Under the IRB approach, the exposure value E is the bank’s own estimate of EAD for the counterparty exposure before allowing for netting, and the value E* after adjusting for onbalance sheet netting forms part of the bank’s total net EAD for that counterparty.
BPR132 21 Part D: Treatment of guarantees and credit derivatives under standardised and IRB approaches D1 Treatment of guarantees and credit derivatives under standardised approach D1.1 Introduction and application
BPR132 22 i. a sovereign or central bank: ii. a public sector entity: iii. a lowest risk multilateral development bank and supranationals, or other development banks; iv. a bank: v. a corporate with an issuer rating corresponding to a rating grade of 1 or 2 under Part B of BPR131; and b. the credit protection provider is not a connected person of the bank. 2. A bank using the standardised approach may take account of a guarantee or credit derivative only if it– a. represents a direct claim on the protection provider; and b. is explicitly referenced to a specific exposure, or to a pool of exposures, (the underlying exposure), so that the extent of the cover is clearly defined and incontrovertible; and c. is legally enforceable; and Guidance: This means, in the case of a guarantee, that the guarantee must be actually posted and/or provided. A commitment to provide a guarantee is not sufficient. d. is irrevocable; and Guidance: This means that there must be no clause that would allow the protection provider to cancel cover unilaterally or that would increase the effective cost of cover as a result of deteriorating credit quality in the hedged exposure. e. is unconditional; and Guidance: This means that there must be no provisions in the contract that could prevent the protection provider from being obliged to make immediate payment should the original counterparty fail to make payments due. f. meets the additional requirements set out in section D1.3 (in the case of a guarantee) or sections D1.4 to D1.7 (in the case of a credit derivative). D1.3 Additional eligibility requirements for guarantees The additional requirements that apply to a guarantee are that the guarantee must– a. cover all types of payment the obligor is required to make under the documentation for the underlying exposure; and
BPR132 23 Guidance: This will include, for example, interest, margin payments, and similar types of payments. b. provide that, on the qualifying default of, or non-payment by, the obligor, any monies outstanding on the underlying exposure can be pursued immediately, without the need for legal action to be taken. Guidance: In these cases, the guarantor may assume the future payment obligations of the obligor covered by the guarantee or may make one lump sum payment. D1.4 Eligible types of credit derivative
BPR132 24 2. However, if the terms of a credit derivative cover the matters specified in subsection (1)(a) and (b), but do not cover the matters specified in subsection (1)(c)), partial recognition of the credit derivative is allowed as follows: a. if the amount of the protection provided by the credit derivative is less than or equal to the amount of the underlying exposure, 60% of the credit derivative protection amount may be recognised: b. if the amount of the credit protection provided is larger than the amount of the underlying exposure, a maximum of 60% of the value of the underlying exposure may be recognised as protected. Guidance: Sections D1.9 and D1.10 also provide adjustments to the amount of credit protection that is recognised, and section D1.11 sets out the method of recognition when the adjusted amount of credit protection is less than the exposure. 3. If the terms of a credit derivative do not meet the conditions in either subsection (1) or subsection (2), it must not be recognised for RWA calculation purposes. Guidance: This means that a credit derivative is not recognised if it does not cover either the credit events set out in subsection (1)(a), or the credit events set out in subsection (1)(b), or both. D1.6 Cash-settled credit derivatives A credit derivative allowing for cash settlement will be recognised as credit risk mitigation for RWA calculation purposes only if the bank has implemented– a. a robust valuation process, which will estimate loss reliably; and b. a clearly specified period for obtaining a post-credit-event valuation of the underlying exposure. D1.7 Asset mismatch in relation to credit derivative
BPR132 25 3. An asset mismatch occurs when– a. a bank has purchased credit protection by way of a credit derivative; and b. the underlying exposure protected by the credit derivative is different from the reference obligation specified in the derivative contract. 4. In this section, reference obligation means any one of the following in relation to a credit derivative: a. the deliverable obligation: b. in the case of a cash-settled credit derivative, the obligation used for the purposes of determining cash settlement: c. the obligation used for the purposes of determining whether a credit event has occurred. D1.8 Treatment of cash-funded credit-linked notes
BPR132 26 b. if the credit protection is marked to market less frequently than daily, 8% scaled up according to the frequency of revaluation using the following formula: HFX = 8% x √ 𝑁𝑅+9 10 where NR is the actual number of working days between revaluations. Guidance: This formula is based on the formula for adjusting haircuts in the treatment of collateral in section B2.5, but without any adjustment for different holding periods. D1.10 Maturity mismatch adjustment If the effective residual maturity of the guarantee or credit derivative is less than that of the underlying exposure, the amount of protection provided must be reduced using the approach, and subject to the conditions, set out in Part E. D1.11 Method of recognition in RWA calculation
BPR132 27 b. however, if the bank takes the first loss on the exposure, the bank may not recognise the credit protection for RWA purposes, and the underlying exposure must be assigned the risk weight applicable to the underlying obligor. Guidance: The bank takes the first loss if, in the case of a guarantee, the bank can only claim on the guarantee if losses exceed the unprotected part of the claim or, in the case of a credit derivative, if the protected portion ranks after the unprotected portion. D2 Treatment of guarantees and credit derivatives under IRB approach D2.1 Use of guarantees and credit derivatives under IRB approach
BPR132 28 b. remain in force until the obligations of the credit protection provider under the guarantee or credit derivative are satisfied in full (to the extent of its amount and tenor); and c. be legally enforceable against the credit protection provider in a jurisdiction where– i. the protection provider has sufficient assets to meet its obligations under the credit protection arrangement; and ii. the bank has a legal ability to access those assets if the protection provider fails to comply with a judgement against it; and d. in the case of a credit derivative, meet the additional requirements set out in section D2.8. 5. Despite subsection (4)(a) to (c), a conditional guarantee (a guarantee prescribing conditions under which the guarantor may not be obliged to perform) may be recognised if the bank can demonstrate that the methodology for adjusting PD or LGD estimates adequately addresses any potential reduction in the credit risk mitigation effect. D2.3 Guarantees and credit derivatives: reflection in PD or LGD estimates
BPR132 29 Guidance: This prohibition reflects the fact that the Reserve Bank has specified regulatory minimum LGDs for both farm lending (see sections C3.1(4) and C3.2 of BPR133) and residential mortgage lending (see section D3.2(4) of BPR133). 4. Where a bank adjusts an LGD estimate, the bank must use the PD estimate and risk-weight function applicable to the underlying obligor for both the protected and unprotected portions of the exposure. 5. Where adjustments are made to PD estimates, the bank must use the substitution approach to determine the capital charge for the protected and unprotected portions, in accordance with subsections (6) and (7) respectively. 6. For the protected portion of the exposure, the bank must calculate the risk weight as follows: a. the bank must calculate the capital charge using the risk-weight function appropriate to the credit protection provider; and b. the bank may, subject to the requirements specified in section C2.2 of BPR133, use a value of PD that is either– i. the PD associated with the bank’s internal obligor grade for the credit protection provider; or ii. if the bank deems that full substitution is not warranted, the PD associated with a grade between that of the underlying obligor and the credit protection provider; and c. the bank may replace the LGD of the underlying exposure with the LGD applicable to the guarantee or credit derivative, taking into account its seniority and any eligible collateral. 7. For the unprotected portion of the exposure, the bank must calculate the risk weight in the same manner as for a direct exposure to the underlying obligor. 8. Whichever risk-weight functions the bank uses in applying the methodology in subsections (4) to (7), the value for maturity (M) that the bank uses in the formula must be the same M that it would use for calculating the RWA for the underlying exposure without a guarantee or credit derivative. D2.4 Ratings of obligor and credit protection provider
BPR132 30 Guidance: For further document and information requirements, see, for example subpart C4 of BPR134. 2. In the case of retail exposures, these requirements also apply to the assignment of an exposure to a pool, and the estimation of PD. D2.6 Guarantees and credit derivatives: limits on adjustments of PD or LGD
BPR132 31 a. require that the exposure on which the protection is based (the reference obligation: see section D1.7(4)) cannot be different from the underlying exposure unless the conditions detailed in section D1.7 are met; and b. address the payout structure of the credit derivative, and conservatively assess the impact this has on the level and timing of recoveries; and c. consider the extent to which other forms of residual credit risk remain; and d. require that the terms of the credit derivative cover all of the credit events specified in section D1.5(1), unless the restructuring of the underlying exposure is not covered, in which case the adjustment criteria may provide for partial recognition as detailed in section D1.5(2). D2.9 Effect of adjustments on EL calculation In calculating the expected loss (EL) for an exposure that is wholly or partly protected by a guarantee or credit derivative, the bank must use the same estimates of PD, LGD, and EAD as those used in calculating the RWA for unexpected loss (UL), after taking account of any adjustments provided for in section D2.3. Guidance: The EL methodology is set out in Part F of BPR133. Where PD or LGD differs between protected and unprotected portions of an exposure, the EL must be calculated separately for the two portions.
BPR132 32 Part E: Maturity mismatch E1 Meaning and adjustments E1.1 Meaning of maturity mismatch
BPR132 33 purposes if its effective original maturity matches that of the underlying exposure. 2. In this Part, effective original maturity means the length of the period– a. beginning on the day on which the credit risk mitigant was first put in place; and b. ending on the day that was specified, when the mitigant was first put in place, as that mitigant’s date of maturity. Guidance: If a bank uses the simple approach to collateral (see subpart B3), collateral with a maturity mismatch must not be recognised. This means that the adjustment approach provided for in this Part does not apply in those circumstances. E1.4 Maturity mismatch adjustment If the effective original maturity of the credit risk mitigant is 12 months or more, credit risk mitigation with a maturity mismatch may be recognised for RWA calculation purposes, but the value of the mitigant must be adjusted using the following formula: PA = P x Max [0, (t - 0.25) / (T - 0.25)] where— PA is the amount of credit protection adjusted for maturity mismatch P is the amount of credit protection that may be recognised after making the relevant adjustments required by Parts B to D, but before taking into account the maturity mismatch Guidance: These adjustments include, for example, haircuts (see sections B2.3 to B2.7) and currency mismatches (see section D1.9). t is the lesser of T and the effective residual maturity of the mitigant, expressed in years T is the lesser of 5 and the effective residual maturity of the underlying exposure expressed in years. Guidance: The application of this formula means that no recognition may be given to credit risk mitigation with a maturity mismatch if its residual maturity is 0.25 years (ie 3 months) or less.