DBRS Morningstar Confirms Ratings on Tower Bridge Funding No. 4 PLC

DBRS Ratings Limited (DBRS Morningstar) confirmed the following ratings on the notes issued by Tower Bridge Funding No. 4 PLC (the Issuer):

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

The ratings on the Class A and Class B notes address the timely payment of interest and ultimate payment of principal on or before the legal final maturity date in December 2062. The ratings on the Class C, Class D, Class E, and Class F notes address the ultimate payment of interest and principal on or before the legal final maturity date while junior, and timely payment of interest while the senior-most class outstanding.

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 securitisation of mortgage loans originated by Belmont Green Finance Limited (BGFL), a specialist UK mortgage lender that offers a full suite of mortgage products including owner-occupied, buy-to-let, adverse-credit-history, and interest-only loans. The securitised mortgage portfolio comprises first-lien home loans originated by BGFL through its Vida Homeloans brand. BGFL is the named mortgage portfolio servicer but delegates its day-to-day servicing activities to Homeloan Management Limited.

PORTFOLIO PERFORMANCE
As of June 2021, loans two to three months in arrears represented 0.2% of the outstanding portfolio balance and the 90+ delinquency ratio was 1.2%. The cumulative loss ratio was zero.

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 8.5% and 23.2%, respectively.

CREDIT ENHANCEMENT
As of the June 2021 payment date, credit enhancement to the Class A, Class B, Class C, Class D, Class E, and Class F notes was 22.4%, 15.9%, 10.8%, 7.6%, 5.7%, and 4.1%, respectively, up from 19.1%, 13.6%, 9.2%, 6.4%, 4.8%, and 3.4% 12 months prior, respectively. Credit enhancement is provided by subordination of junior classes and the general reserve fund.

The transaction benefits from a reserve fund of GBP 12.5 million and a liquidity reserve fund of GBP 6.0 million. The liquidity reserve fund covers senior fees and interest on the Class A and Class B notes, while the general reserve fund covers senior fees, interest, and principal (via the principal deficiency ledgers) on the rated notes.

BNP Paribas Securities Services SCA, London Branch acts as the account bank for the transaction. Based on the DBRS Morningstar private rating of BNP Paribas Securities Services SCA, 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.

NatWest Markets Plc acts as the swap counterparty for the transaction. DBRS Morningstar's public Long-Term Critical Obligations Rating of NatWest Markets Plc at “A” is above the First Rating Threshold as described in DBRS Morningstar's "Derivative 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 incorporated an increase in probability of default for certain borrower characteristics, and conducted additional sensitivity analysis to determine that the transaction benefits from sufficient liquidity support to withstand potential high levels of payment holidays in the portfolio.

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.

A review of the transaction legal documents was not conducted as the 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: http://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/364527/global-methodology-for-rating-sovereign-governments.

The sources of data and information used for these ratings include investor reports provided by Elavon Financial Services DAC, U.K. Branch, and loan-level data provided by Belmont Green Finance Limited.

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

At the time of the initial rating, 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 10 July 2020, when DBRS Morningstar confirmed the ratings of the Class A, Class B, Class C, Class D, Class E, and Class F notes.

The lead analyst responsibilities for this transaction have been transferred to Natalia Coman.

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 rating, DBRS Morningstar considered the following stress scenarios as compared with the parameters used to determine the rating (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 8.5% and 23.2%, 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 (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 (low) (sf).

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

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

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

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

Class F Risk Sensitivity:
-- 25% increase in LGD, expected rating of B (high) (sf)
-- 50% increase in LGD, expected rating of B (sf)
-- 25% increase in PD, expected rating of B (sf)
-- 50% increase in PD, expected rating below B (sf)
-- 25% increase in PD and 25% increase in LGD, expected rating below B (sf)
-- 25% increase in PD and 50% increase in LGD, expected rating below B (sf)
-- 50% increase in PD and 25% increase in LGD, expected rating below 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: http://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: Natalia Coman, Senior Analyst
Rating Committee Chair: Alfonso Candelas, Senior Vice President
Initial Rating Date: 24 June 2019

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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: http://www.dbrsmorningstar.com/about/methodologies.

-- Legal Criteria for European Structured Finance Transactions (6 April 2021), https://www.dbrsmorningstar.com/research/376314/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.
-- Derivative Criteria for European Structured Finance Transactions (24 September 2020), https://www.dbrsmorningstar.com/research/367092/derivative-criteria-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 http://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.