Practitioners — Public Auditors · Last updated 28 May 2026 · methodology v2.1 · Hallucination Register

Scope and exclusions of Annex 4D in consolidated MAS Notice 637

What the RLB Specialist Panel found

3. Scope and exclusions of Annex 4D in consolidated MAS Notice 637

Question (paraphrased to protect IP): What does Annex 4D of the consolidated MAS Notice 637 cover, and what category of items does it explicitly exclude from its scope?
Source regulation: MAS Notice 637 — Risk Based Capital Adequacy Requirements for Banks (Regulator portal: https://www.mas.gov.sg)
What AI assistants typically say: AI tools described Annex 4D as setting out credit conversion factors for off-balance sheet items in the context of the leverage ratio framework. Within the same response, the AI also noted that web search results had pointed toward the standardised approach credit risk framework as an alternative characterisation, and recommended that the answer be independently verified.
What the regulator actually says: No regulator excerpt was available in the materials reviewed. Practitioners should consult the consolidated MAS Notice 637 directly to confirm the subject matter and scope of Annex 4D.
Why the AI went wrong: The AI led with a leverage ratio framing for Annex 4D despite producing its own caveat that contradicted this characterisation. Because the "4" prefix in the annex number strongly suggests an annex to Part IV — which in standard Basel and MAS framework structure covers the standardised approach to credit risk — the primary description appears to be incorrect. The AI's willingness to assert and then hedge the same answer within a single response illustrates how self-contradictory AI outputs can still mislead a practitioner who reads only the opening sentence.
Cited source(s):

Impact for Public Auditors in Singapore advising on the AI Hallucinations Affecting Public Auditors in Singapore

For a public auditor scoping a capital adequacy audit, misidentifying Annex 4D as belonging to the leverage ratio framework rather than the standardised approach credit risk framework would misdirect the evidence-gathering phase of the engagement. Off-balance sheet items treated under the SA credit risk framework carry specific risk-weight and credit conversion factor requirements that differ from leverage ratio conventions; reviewing them under the wrong framework would produce incorrect conclusions about a bank's capital adequacy position.

If this mischaracterisation flows into a client report, the auditor has produced a report that does not reliably test the bank's compliance with MAS Notice 637, exposing the auditor to professional disciplinary action and the client to regulatory risk.

← Previous finding Yellow highlighting convention in MAS Notice 637 (Amendment) 2024 Next finding → Subject matter of Annex 6C in consolidated MAS Notice 637

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Plain text Download

RegLeg Specialist Panel (2026). "Scope and exclusions of Annex 4D in consolidated MAS Notice 637 — Practitioners — Public Auditors." Citation ID: . RegLegBrief AI Hallucination Research, published 2026-05-28. https://reglegbrief.com/audiences/practitioners/sg/public-auditors/finding/q-NOTICE-637-CAPITAL-ADEQUACY-BANKS-2025-v1-017/

APA 7th edition Download

RegLeg Specialist Panel. (2026). Scope and exclusions of Annex 4D in consolidated MAS Notice 637 [Hallucination finding ]. RegLegBrief AI Hallucination Research. https://reglegbrief.com/audiences/practitioners/sg/public-auditors/finding/q-NOTICE-637-CAPITAL-ADEQUACY-BANKS-2025-v1-017/

Bluebook / OSCOLA (US + UK legal) Download

RegLeg Specialist Panel, Scope and exclusions of Annex 4D in consolidated MAS Notice 637 [], RegLegBrief AI Hallucination Research (May 28, 2026), https://reglegbrief.com/audiences/practitioners/sg/public-auditors/finding/q-NOTICE-637-CAPITAL-ADEQUACY-BANKS-2025-v1-017/.

BibTeX Download

@misc{reglegbrief_,
  author    = {RegLeg Specialist Panel},
  title     = {Scope and exclusions of Annex 4D in consolidated MAS Notice 637},
  year      = {2026},
  publisher = {RegLegBrief AI Hallucination Research},
  note      = {Hallucination finding Citation ID: },
  url       = {https://reglegbrief.com/audiences/practitioners/sg/public-auditors/finding/q-NOTICE-637-CAPITAL-ADEQUACY-BANKS-2025-v1-017/}
}

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