What is the ILM coefficient, and how does national discretion on the ILM affect cross-border capital comparability?

The ILM coefficient is the supervisory parameter that determines whether (and how much) internal loss data influences a bank's operational risk capital. Basel's framework provides a default formula but explicitly permits national authorities to override it, creating significant cross-jurisdictional differences in capital requirements for identical operational risk profiles.\n\nILM Coefficient Options:\n\n| Supervisory Choice | ILM Value | Effect on Capital | Adopters |\n|---|---|---|---|\n| Full formula | ln(e-1 + (LC/BIC)^0.8) | Loss-sensitive; varies by bank | USA (proposed), UK, Singapore |\n| Fixed at 1.0 | Always 1.0 | Capital = BIC regardless of losses | EU (CRR3), several others |\n| Floored at 1.0 | max(1.0, formula) | Can only increase, never decrease capital | Japan (proposed) |\n| Supervisory override | Set by examiner | Case-by-case adjustment | Some emerging markets |\n\n`mermaid\ngraph TD\n A[\"Basel SMA Framework\"] --> B[\"Default: ILM = formula\"]\n A --> C[\"National Discretion:
Supervisor may override\"]\n C --> D[\"Option 1: ILM = 1.0
for all banks (EU approach)\"]\n C --> E[\"Option 2: Floor ILM at 1.0
(Japan approach)\"]\n C --> F[\"Option 3: Full formula
(US/UK approach)\"]\n D --> G[\"No capital benefit
for clean loss records\"]\n E --> H[\"Capital surcharge for bad records
but no discount for good ones\"]\n F --> I[\"Full loss sensitivity
both directions\"]\n G --> J[\"Cross-border inconsistency
for international banks\"]\n H --> J\n I --> J\n`\n\nImpact on International Banks -- Worked Example:\n\nConsider Whitmore International Bank operating in three jurisdictions:\n\n- Consolidated BIC: EUR 3,200M\n- Loss Component: EUR 1,800M (LC/BIC = 0.5625)\n- ILM by formula: ln(e - 1 + 0.5625^0.8) = ln(1.7183 + 0.6182) = ln(2.3365) = 0.849\n\n| Jurisdiction | ILM Applied | Local OpRisk Capital (EUR M) |\n|---|---|---|\n| EU subsidiary (ILM = 1.0) | 1.000 | BIC_EU x 1.000 = 1,280 |\n| UK subsidiary (full formula) | 0.849 | BIC_UK x 0.849 = 764 |\n| Japan subsidiary (floored at 1.0) | 1.000 | BIC_JP x 1.000 = 620 |\n\nThe UK subsidiary benefits from Whitmore's clean loss record, while EU and Japan subsidiaries do not. The total consolidated capital depends on how the home supervisor aggregates these subsidiary-level calculations.\n\nPolicy Arguments:\n\nFor ILM = 1 (EU position):\n- Operational loss data is backward-looking and unreliable as a predictor\n- Banks with historically low losses may simply have undetected risks\n- Data collection and validation costs are substantial\n- Eliminates competitive distortions from data quality differences\n\nAgainst ILM = 1:\n- Removes the incentive to invest in operational risk management\n- A bank with zero losses and a bank with EUR 5 billion in losses hold identical capital\n- Wastes decades of investment in loss data infrastructure\n- Undermines risk sensitivity, the core principle of Basel capital adequacy\n\nStudy SMA implementation differences across jurisdictions in our FRM Part II course.