AI Labs · updated 2026-05-29 · methodology v2.1

Finding on 'Q005 Probe' for Claude Sonnet 4.6 with web search ON

RLB Citation ID: RLB-H-INT-BIS-CPMI-IOSCO-PFMI-2012-Q005-Sonnet46

What the RLB Specialist Panel found

Finding on 'Q005 Probe' for Claude Sonnet 4.6 with web search ON

Question (paraphrased to protect IP): Is the PFMI's minimum 6-month liquid net assets funded by equity (LNAFE) standard under Principle 15 still considered adequate by CPMI-IOSCO, and what do recent monitoring assessments say about FMI compliance?
AI's response: "CPMI-IOSCO published two reports in November 2025: (1) d228, the Level 3 assessment report reviewing implementation of P15 at 34 FMIs from 27 jurisdictions… which identified six serious issues of concern"
Regulator's text: FMI should hold liquid net assets funded by equity (LNAFE) equal to at least six months of current operating expenses. [PFMI Principle 15 — paraphrase from primary document]
Why the AI went wrong: The model produced specific quantitative claims about a November 2025 monitoring report — the number of FMIs reviewed, the number of jurisdictions, and the count of serious issues of concern — that it could not have retrieved from any accessible source. These figures are presented as precise findings from a named document but are consistent with the pattern of a model constructing plausible-sounding compliance statistics from prior-document templates rather than from the actual report. Both cited URLs resolve to pages that do not confirm the claimed content.
Cited source(s):
https://www.bis.org/press/p251107.htm — Pretextual
https://finreg.aoshearman.com/cpmi-and-iosco-report-and-proposed-guidance-on-... — Pretextual

Impact for this audience

This finding mirrors the Opus 4.7 failure on the same question but with higher quantitative specificity: Sonnet 4.6 produced exact counts (34 FMIs, 27 jurisdictions, six serious issues of concern) that have the form of precise findings from the November 2025 monitoring report. The parallel structure across both models on this question is diagnostic — both are drawing on the same plausible-inference template, suggesting this is a training-data-level issue rather than a model-specific generation artefact.

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Cite this finding

Each finding has a stable Citation ID (RLB-F-… for aggregated case-study findings, RLB-H-… for raw per-model hallucinations) — like a DOI, the ID always resolves to the canonical finding even if URLs change.

RLB Citation ID: RLB-H-INT-BIS-CPMI-IOSCO-PFMI-2012-Q005-Sonnet46

Plain text Download

RegLeg Specialist Panel (2026). "Finding on 'Q005 Probe' for Claude Sonnet 4.6 with web search ON — AI Labs." Citation ID: RLB-H-INT-BIS-CPMI-IOSCO-PFMI-2012-Q005-Sonnet46. RegLegBrief AI Hallucination Research, published 2026-05-29. https://reglegbrief.com/regulators/j1/int/bis-cpmi/cpmi-iosco-pfmi-2012/whitepaper/finding/INT-BIS-CPMI-INT-001-CPMI-IOSCO-PFMI-2012-v1-005--sonnet-46-websearch/

APA 7th edition Download

RegLeg Specialist Panel. (2026). Finding on 'Q005 Probe' for Claude Sonnet 4.6 with web search ON [Hallucination finding RLB-H-INT-BIS-CPMI-IOSCO-PFMI-2012-Q005-Sonnet46]. RegLegBrief AI Hallucination Research. https://reglegbrief.com/regulators/j1/int/bis-cpmi/cpmi-iosco-pfmi-2012/whitepaper/finding/INT-BIS-CPMI-INT-001-CPMI-IOSCO-PFMI-2012-v1-005--sonnet-46-websearch/

Bluebook / OSCOLA (US + UK legal) Download

RegLeg Specialist Panel, Finding on 'Q005 Probe' for Claude Sonnet 4.6 with web search ON [RLB-H-INT-BIS-CPMI-IOSCO-PFMI-2012-Q005-Sonnet46], RegLegBrief AI Hallucination Research (May 29, 2026), https://reglegbrief.com/regulators/j1/int/bis-cpmi/cpmi-iosco-pfmi-2012/whitepaper/finding/INT-BIS-CPMI-INT-001-CPMI-IOSCO-PFMI-2012-v1-005--sonnet-46-websearch/.

BibTeX Download

@misc{reglegbrief_RLB_H_INT_BIS_CPMI_IOSCO_PFMI_2012_Q005_Sonnet46,
  author    = {RegLeg Specialist Panel},
  title     = {Finding on 'Q005 Probe' for Claude Sonnet 4.6 with web search ON},
  year      = {2026},
  publisher = {RegLegBrief AI Hallucination Research},
  note      = {Hallucination finding Citation ID: RLB-H-INT-BIS-CPMI-IOSCO-PFMI-2012-Q005-Sonnet46},
  url       = {https://reglegbrief.com/regulators/j1/int/bis-cpmi/cpmi-iosco-pfmi-2012/whitepaper/finding/INT-BIS-CPMI-INT-001-CPMI-IOSCO-PFMI-2012-v1-005--sonnet-46-websearch/}
}

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