Line4

1 min readBlockingBank of England banking taxonomy 4.1.1Updated 11 November 2026

MREL Debt: the format of a code or text (BR01.00.01.01, Bank of England check boe_b4110)

A blocking check on the MREL Debt template (BR01.00.01.01), in the MREL debt (MRL003) return.

Line4 Check runs it on the MREL debt (MRL003) return, proven on test files, check by check: the same outcome on all eight test files of that return.

Check your file for this ruleWhat to do if it fails

The rule in plain words

Subject to the entry within column 333, please enter the relevant Legal entity identification code using a valid format (LEI/20 alpha-numeric characters). If an LEI doesn't exist, please provide a SC code (i.e. SC/123456ABC). For debt securities that fall under the category of other, please enter Not Applicable (with capitalised N and A)

The headline gives only the template and the kind of check, because the rule is too long to say in a headline. The plain words above say all of it.

What to do if your return fails it

  1. 01Open the table below and find the cells the rule reads.
  2. 02Compare the code or text in your return with the format the rule sets out, character by character, including any prefix and any spaces.
  3. 03It runs only when your filing indicators mark BR01.00.01 as reported.
  4. 04This is a blocking check. A return that fails it is normally rejected, so fix it before you submit.

The cells it reads

MREL Debt (BR01.00.01.01)

Column

  • C335Form of the security - Identification

Which returns it applies to

Line4 Check runs it on the MREL debt (MRL003) return on Bank of England banking taxonomy 4.1.1. The Bank of England applies it to MREL debt (MRL003) returns, as a blocking check.

The Bank’s own words and formula

The plain words above are the Bank of England’s own, word for word, from its list of validations.

Show the formulaShow

The Bank of England's formula. Cells are written as {t: table, r: row, c: column}.

matches({t: BR01.00.01.01, c: 335}, "^LEI/[A-Z0-9]{20}$") or matches({t: BR01.00.01.01, c: 335}, "^SC/.*") or matches({t: BR01.00.01.01, c: 335}, "^Not Applicable$")

Every PRA banking rule on BR01.00.01.01

Checks like this one, run at the point of submission, are the first step to real-time supervision. Line4 builds SupTech software for financial regulators that runs checks like these as each return arrives.