DBRS Morningstar Confirms Ratings on Warwick Finance Residential Mortgages Number Four Plc

DBRS Ratings Limited (DBRS Morningstar) confirmed its ratings of the notes issued by Warwick Finance Residential Mortgages Number Four Plc (the Issuer) as follows:

-- Class A notes at AAA (sf)
-- Class B notes at AA (sf)
-- Class C notes at A (low) (sf)
-- Class D notes at BBB (high) (sf)
-- Class E notes at BB (high) (sf)

The rating on the Class A notes addresses the timely payment of interest and the ultimate payment of principal on or before the legal final maturity date in March 2042. The rating on the Class B notes addresses the ultimate payment of interest and principal while junior, and the timely payment of interest while the senior-most class outstanding. The ratings on the Class C, Class D, and Class E notes address the ultimate payment of interest and principal.

The rating actions follow an annual review of the transaction and are based on the following analytical considerations:
-- Portfolio performance, in terms of delinquencies, defaults, and losses.
-- Portfolio default rate (PD), loss given default (LGD), and expected loss assumptions on the remaining receivables.
-- Current available credit enhancement to the notes to cover the expected losses at their respective rating levels.
-- Current economic environment and an assessment of sustainable performance, as a result of the Coronavirus Disease (COVID-19) pandemic.

The Issuer is a bankruptcy-remote special-purpose vehicle incorporated in the United Kingdom. The issued notes were used to fund the purchase of seasoned owner-occupied and buy-to-let nonconforming portfolios of mortgages originated in the UK by Platform Funding Limited, Verso Limited, Kensington Mortgage Company Limited, Southern Pacific Mortgages Limited, and GMAC-RFC Limited (now Paratus AMC Limited). The loans were sold to the issuer at transaction close by The Co-operative Bank plc and are serviced by Western Mortgages Services Limited.

PORTFOLIO PERFORMANCE
As of June 2021, loans two to three months in arrears represented 0.5% of the outstanding portfolio balance and the 90+ delinquency ratio was 3.3%. As of the same date, the cumulative loss ratio was 0.1%.

PORTFOLIO ASSUMPTIONS AND KEY DRIVERS
DBRS Morningstar conducted a loan-by-loan analysis of the remaining pool of receivables and has updated its base case PD and LGD assumptions to 10.6% and 14.2%, respectively.

CREDIT ENHANCEMENT
As of the June 2021 payment date, the credit enhancements available to the Class A, Class B, Class C, Class D, and Class E notes were 18.2%, 12.7%, 9.0%, 7.2%, and 5.4%, respectively, up from 16.2%, 11.3%, 8.0%, 6.4%, and 4.7%, 12 months prior, respectively. Credit enhancement is provided by subordination of junior classes and the residual certificates.

The transaction benefits from a liquidity reserve fund of GBP 2.8 million, available to cover senior fees and interest on the Class A and Class B notes.

Citibank N.A., London Branch acts as the account bank for the transaction. Based on the DBRS Morningstar private rating of Citibank N.A., London Branch; the downgrade provisions outlined in the transaction documents; and other mitigating factors inherent in the transaction structure, DBRS Morningstar considers the risk arising from the exposure to the account bank to be consistent with the rating assigned to the Class A notes, as described in DBRS Morningstar's "Legal Criteria for European Structured Finance Transactions" methodology.

DBRS Morningstar analysed the transaction structure in Intex DealMaker.

The Coronavirus Disease (COVID-19) and the resulting isolation measures have caused an economic contraction, leading in some cases to increases in unemployment rates and income reductions for borrowers. DBRS Morningstar anticipates that delinquencies may continue to increase in the coming months for many structured finance transactions, some meaningfully. The ratings are based on additional analysis and, where appropriate, adjustments to expected performance as a result of the global efforts to contain the spread of the coronavirus.

For this transaction, DBRS Morningstar increased the expected default rate for self-employed borrowers, and assessed a potential reduction in portfolio prepayment rates.

On 16 April 2020, the DBRS Morningstar Sovereign group released a set of macroeconomic scenarios for the 2020–22 period in select economies. These scenarios were last updated on 18 June 2021. For details, see the following commentaries: https://www.dbrsmorningstar.com/research/380281/global-macroeconomic-scenarios-june-2021-update and https://www.dbrsmorningstar.com/research/359903/global-macroeconomic-scenarios-application-to-credit-ratings. The DBRS Morningstar analysis considered impacts consistent with the moderate scenario in the referenced reports.

On 14 June 2021, DBRS Morningstar updated its 5 May 2020 commentary outlining the impact of the coronavirus crisis on performance of DBRS Morningstar-rated RMBS transactions in Europe one year on. For more details, please see: https://www.dbrsmorningstar.com/research/380094/the-impact-of-covid-19-on-european-mortgage-performance-one-year-on and https://www.dbrsmorningstar.com/research/360599/european-rmbs-transactions-risk-exposure-to-coronavirus-covid-19-effect.

For more information regarding rating methodologies and Coronavirus Disease (COVID-19), please see the following DBRS Morningstar press release: https://www.dbrsmorningstar.com/research/357883.

For more information regarding the structured finance rating approach and Coronavirus Disease (COVID-19), please see the following DBRS Morningstar press release: https://www.dbrsmorningstar.com/research/359905.

For more information regarding structured finance rating methodologies and Coronavirus Disease (COVID-19), please see the following DBRS Morningstar press release: https://www.dbrsmorningstar.com/research/358308.

ESG CONSIDERATIONS
A description of how DBRS Morningstar considers ESG factors within the DBRS Morningstar analytical framework can be found in the DBRS Morningstar Criteria: Approach to Environmental, Social, and Governance Risk Factors in Credit Ratings at: https://www.dbrsmorningstar.com/research/373262.

Notes:
All figures are in British pound sterling unless otherwise noted.

The principal methodology applicable to the ratings is the “Master European Structured Finance Surveillance Methodology” (8 February 2021).

DBRS Morningstar has applied the principal methodology consistently and conducted a review of the transaction in accordance with the principal methodology.

DBRS Morningstar conducted a review of the amended transaction documents following the implementation of SONIA-linked benchmark rates and amended margins on the rated notes, executed on 26 July 2021 and effective as of the March 2022 interest payment date. A review of the remaining transaction legal documents was not conducted as these legal documents have remained unchanged since the most recent rating action.

Other methodologies referenced in this transaction are listed at the end of this press release. These may be found at: https://www.dbrsmorningstar.com/about/methodologies.

For a more detailed discussion of the sovereign risk impact on Structured Finance ratings, please refer to “Appendix C: The Impact of Sovereign Ratings on Other DBRS Morningstar Credit Ratings” of the “Global Methodology for Rating Sovereign Governments” at: https://www.dbrsmorningstar.com/research/381451/global-methodology-for-rating-sovereign-governments.

The sources of data and information used for these ratings include investor reports and loan-level data provided by The Co-operative Bank plc.

DBRS Morningstar did not rely upon third-party due diligence in order to conduct its analysis.

At the time of the initial ratings, DBRS Morningstar was supplied with third-party assessments. However, this did not impact the rating analysis.

DBRS Morningstar considers the data and information available to it for the purposes of providing these ratings to be of satisfactory quality.

DBRS Morningstar does not audit or independently verify the data or information it receives in connection with the rating process.

The last rating action on this transaction took place on 21 August 2020, when DBRS Morningstar confirmed the ratings of the Class A, Class B, Class C, Class D, and Class E notes.

Information regarding DBRS Morningstar ratings, including definitions, policies, and methodologies, is available at www.dbrsmorningstar.com.

To assess the impact of changing the transaction parameters on the ratings, DBRS Morningstar considered the following stress scenarios as compared with the parameters used to determine the ratings (the Base Case):

-- DBRS Morningstar expected a lifetime base case PD and LGD for the pool based on a review of the current assets. Adverse changes to asset performance may cause stresses to base case assumptions and therefore have a negative effect on credit ratings.
-- The base case PD and LGD of the current pool of loans for the Issuer are 10.6% and 14.2%, respectively.
-- The risk sensitivity overview below illustrates the ratings expected if the PD and LGD increase by a certain percentage over the base case assumption. For example, if the LGD increases by 50%, the rating of the Class A notes would be expected to fall to AA (high) (sf), assuming no change in the PD. If the PD increases by 50%, the rating of the Class A notes would be expected to fall to AA (sf), assuming no change in the LGD. Furthermore, if both the PD and LGD increase by 50%, the rating of the Class A notes would be expected to fall to A (high) (sf).

Class A Risk Sensitivity:
-- 25% increase in LGD, expected rating of AAA (sf)
-- 50% increase in LGD, expected rating of AA (high) (sf)
-- 25% increase in PD, expected rating of AAA (sf)
-- 50% increase in PD, expected rating of AA (sf)
-- 25% increase in PD and 25% increase in LGD, expected rating of AA (sf)
-- 25% increase in PD and 50% increase in LGD, expected rating of AA (low) (sf)
-- 50% increase in PD and 25% increase in LGD, expected rating of A (high) (sf)
-- 50% increase in PD and 50% increase in LGD, expected rating of A (high) (sf)

Class B Risk Sensitivity:
-- 25% increase in LGD, expected rating of A (high) (sf)
-- 50% increase in LGD, expected rating of A (sf)
-- 25% increase in PD, expected rating of A (high) (sf)
-- 50% increase in PD, expected rating of A (low) (sf)
-- 25% increase in PD and 25% increase in LGD, expected rating of A (low) (sf)
-- 25% increase in PD and 50% increase in LGD, expected rating of BBB (high) (sf)
-- 50% increase in PD and 25% increase in LGD, expected rating of BBB (high) (sf)
-- 50% increase in PD and 50% increase in LGD, expected rating of BBB (sf)

Class C Risk Sensitivity:
-- 25% increase in LGD, expected rating of BBB (high) (sf)
-- 50% increase in LGD, expected rating of BBB (sf)
-- 25% increase in PD, expected rating of BBB (high) (sf)
-- 50% increase in PD, expected rating of BBB (sf)
-- 25% increase in PD and 25% increase in LGD, expected rating of BBB (sf)
-- 25% increase in PD and 50% increase in LGD, expected rating of BBB (low) (sf)
-- 50% increase in PD and 25% increase in LGD, expected rating of BB (high) (sf)
-- 50% increase in PD and 50% increase in LGD, expected rating of BB (high) (sf)

Class D Risk Sensitivity:
-- 25% increase in LGD, expected rating of BBB (low) (sf)
-- 50% increase in LGD, expected rating of BB (high) (sf)
-- 25% increase in PD, expected rating of BB (high) (sf)
-- 50% increase in PD, expected rating of BB (high) (sf)
-- 25% increase in PD and 25% increase in LGD, expected rating of BB (high) (sf)
-- 25% increase in PD and 50% increase in LGD, expected rating of BB (high) (sf)
-- 50% increase in PD and 25% increase in LGD, expected rating of BB (sf)
-- 50% increase in PD and 50% increase in LGD, expected rating of BB (low) (sf)

Class E Risk Sensitivity:
-- 25% increase in LGD, expected rating of BB (low) (sf)
-- 50% increase in LGD, expected rating of B (high) (sf)
-- 25% increase in PD, expected rating of BB (low) (sf)
-- 50% increase in PD, expected rating of B (high) (sf)
-- 25% increase in PD and 25% increase in LGD, expected rating of B (high) (sf)
-- 25% increase in PD and 50% increase in LGD, expected rating of B (sf)
-- 50% increase in PD and 25% increase in LGD, expected rating of B (sf)
-- 50% increase in PD and 50% increase in LGD, expected rating below B (sf)

For further information on DBRS Morningstar historical default rates published by the European Securities and Markets Authority (ESMA) in a central repository, see: https://cerep.esma.europa.eu/cerep-web/statistics/defaults.xhtml. DBRS Morningstar understands further information on DBRS Morningstar historical default rates may be published by the Financial Conduct Authority (FCA) on its webpage: https://www.fca.org.uk/firms/credit-rating-agencies.

These ratings are endorsed by DBRS Ratings GmbH for use in the European Union.

Lead Analyst: Andrew Lynch, Vice President
Rating Committee Chair: Alfonso Candelas, Senior Vice President
Initial Rating Date: 23 August 2019

DBRS Ratings Limited
20 Fenchurch Street
31st Floor
London EC3M 3BY
United Kingdom
Tel. +44 (0) 20 7855 6600
Registered and incorporated under the laws of England and Wales: Company No. 7139960.

The rating methodologies used in the analysis of this transaction can be found at: https://www.dbrsmorningstar.com/about/methodologies.

-- Legal Criteria for European Structured Finance Transactions (29 July 2021), https://www.dbrsmorningstar.com/research/382171/legal-criteria-for-european-structured-finance-transactions.
-- Master European Structured Finance Surveillance Methodology (8 February 2021), https://www.dbrsmorningstar.com/research/373435/master-european-structured-finance-surveillance-methodology.
-- Operational Risk Assessment for European Structured Finance Servicers (19 November 2020), https://www.dbrsmorningstar.com/research/370270/operational-risk-assessment-for-european-structured-finance-servicers.
-- European RMBS Insight Methodology (3 June 2021) and European RMBS Insight Model v5.2.0.0, https://www.dbrsmorningstar.com/research/379557/european-rmbs-insight-methodology.
-- European RMBS Insight: UK Addendum (9 October 2020), https://www.dbrsmorningstar.com/research/368132/european-rmbs-insight-uk-addendum.
-- Interest Rate Stresses for European Structured Finance Transactions (28 September 2020), https://www.dbrsmorningstar.com/research/367292/interest-rate-stresses-for-european-structured-finance-transactions.
-- DBRS Morningstar Criteria: Approach to Environmental, Social, and Governance Risk Factors in Credit Ratings (3 February 2021), https://www.dbrsmorningstar.com/research/373262/dbrs-morningstar-criteria-approach-to-environmental-social-and-governance-risk-factors-in-credit-ratings.

A description of how DBRS Morningstar analyses structured finance transactions and how the methodologies are collectively applied can be found at https://www.dbrsmorningstar.com/research/278375.

For more information on this credit or on this industry, visit www.dbrsmorningstar.com or contact us at info@dbrsmorningstar.com.