Practitioners — Accountants (CA/PA) · Last updated 28 May 2026 · methodology v2.1 · Hallucination Register

Content and scope of Annex 4D of consolidated MAS Notice 637

What the RLB Specialist Panel found

3. Content and scope of Annex 4D of 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: The AI described Annex 4D as setting out credit conversion factors for off-balance sheet items within the leverage ratio framework, while also acknowledging in the same response that search results had pointed toward the standardised approach credit risk framework instead.
What the regulator actually says: No regulator excerpt was available for direct quotation; practitioners should consult the consolidated MAS Notice 637 on the MAS portal at https://www.mas.gov.sg for the definitive annex content.
Why the AI went wrong: The AI led with a leverage ratio characterisation while its own internal search results suggested a credit risk framing — a self-contradictory response that reveals the AI was inferring rather than retrieving. The "4" prefix of the annex number is consistent with Part IV of the notice (standardised approach to credit risk), which the AI's own caveat acknowledged. A practitioner who noted only the primary answer and not the caveat would act on a likely-incorrect characterisation of the annex's scope.
Cited source(s):

Impact for Accountants (CA/PA) in Singapore advising on the AI Hallucinations Affecting Accountants (CA/PA) in Singapore

An Accountants (CA/PA) preparing or reviewing a bank client's off-balance-sheet exposure disclosures could mischaracterise the applicable framework based on the AI's self-contradictory Annex 4D description — applying leverage ratio logic where the standardised approach to credit risk was required, or vice versa. A capital adequacy calculation prepared on the wrong framework basis could produce materially incorrect capital ratios. For a practitioner whose advice informs a regulatory capital return, an error of this kind could expose both the practitioner and the bank client to MAS supervisory action.

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RegLeg Specialist Panel (2026). "Content and scope of Annex 4D of consolidated MAS Notice 637 — Practitioners — Accountants (CA/PA)." Citation ID: . RegLegBrief AI Hallucination Research, published 2026-05-28. https://reglegbrief.com/audiences/practitioners/sg/accountants-ca-pa/finding/q-NOTICE-637-CAPITAL-ADEQUACY-BANKS-2025-v1-017/

APA 7th edition Download

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

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

BibTeX Download

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

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