1 min readWarningBank of England taxonomy 2.2.0Updated 11 November 2026

Cyber underwriting risk: the Sum(s) insured (C0080) should typically be greater than or equal to the Sum(s) reinsured (C100) (IR.21.04, Bank of England rule IR_bv0115)

A warning on the cyber underwriting risk template (IR.21.04), in the annual solo (ARS) and annual third-country branch (ARB) returns.

The rule in plain words

The Sum(s) insured (C0080) should typically be greater than or equal to the Sum(s) reinsured (C100)

What to do if your return fails it

  1. 01Open the table below and find the cells the rule reads.
  2. 02Compare the values in your return. If the first is smaller than it may be, one of them is wrong: check both before you change either.
  3. 03It runs only when your filing indicators mark IR.21.04 as reported.
  4. 04This is a warning. It does not stop the return on its own, but your supervisor may ask you to explain it.

The cells it reads

Cyber underwriting risk - risk identification (IR.21.04.01.01)

Columns

  • C0080Sum(s) insured
  • C0100Sum(s) reinsured

Which returns it applies to

Line4 Check runs it on annual solo (ARS) and annual third-country branch (ARB) returns on Bank of England taxonomy 2.2.0. The Bank of England applies it to annual solo (ARS) and annual third-country branch (ARB) returns, as a warning.

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}.

{t: IR.21.04.01.01, c: C0080} >= {t: IR.21.04.01.01, c: C0100}

Every Solvency UK rule on IR.21.04

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.