AI Hallucination Research › Regulators › Major advanced economies › US › CFTC › FCM-DCO-CUSTOMER-FUNDS-INVESTMENTS-REG-1-25-2024 › White paper › Detail › Finding
AI Labs · updated 2026-06-04 · methodology v2.1

Finding on 'Q001 Probe' for Claude Opus 4.7 with web search ON

RLB Citation ID: RLB-H-US-CFTC-FCM-DCO-CUSTOMER-FUNDS-INVESTMENTS-REG-1-25-2024-Q001-Opus47
What the RLB Specialist Panel found

Finding on 'Q001 Probe' for Claude Opus 4.7 with web search ON

  • Question (paraphrased to protect IP): What are the updated concentration limits that apply to government money market funds and Treasury ETFs under the 2024 Regulation 1.25 amendments, including any tiered or size-based thresholds based on fund and management company asset sizes?
  • AI's response: "the final rule did not adopt tiered or FCM-size-based thresholds — the percentage limits apply uniformly regardless of FCM size"
  • Regulator's text: Investments in government money market funds or qualified ETFs whose assets are ≥$1B and whose management company manages ≥$25B: may not exceed 50% of total segregated assets.
  • Why the AI went wrong: The model answered as if the final rule preserved the uniform-threshold structure of prior Regulation 1.25 and rejected size-based differentiation — a description that fits early-stage rulemaking commentary but not the final amended text. The rule introduces an explicit two-condition tier keyed to fund AUM and management company AUM; the model's response overwrites this with a generalised prior-version schema and presents the overwrite as a confirmed regulatory outcome.
  • Cited source(s):
Impact for this audience

This finding implicates the training corpus's representation of the final rule text relative to pre-final secondary commentary. The model asserted that the final rule rejected size-based tiering — a claim that reflects early rulemaking commentary, not the published final rule. The retrieval pipeline failed to surface the primary rule text at sufficient specificity to override the trained-schema prior, suggesting the Federal Register notice is underweighted relative to secondary sources in retrieval ranking for this query type.

References — raw findings (per AI model)
This finding also affects
Next finding → Finding on 'Q002 Probe' for Claude Opus 4.7 with web search ON
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-US-CFTC-FCM-DCO-CUSTOMER-FUNDS-INVESTMENTS-REG-1-25-2024-Q001-Opus47
Plain text Download 
RegLeg Specialist Panel (2026). "Finding on 'Q001 Probe' for Claude Opus 4.7 with web search ON — AI Labs." Citation ID: RLB-H-US-CFTC-FCM-DCO-CUSTOMER-FUNDS-INVESTMENTS-REG-1-25-2024-Q001-Opus47. RegLegBrief AI Hallucination Research, published 2026-06-04. https://reglegbrief.com/regulators/j3/us/cftc/fcm-dco-customer-funds-investments-reg-1-25-2024/whitepaper/finding/US-CFTC-US-001-FCM-DCO-CUSTOMER-FUNDS-INVESTMENTS-REG-1-25-2024-v1-001--opus-47-websearch/
APA 7th edition Download 
RegLeg Specialist Panel. (2026). Finding on 'Q001 Probe' for Claude Opus 4.7 with web search ON [Hallucination finding RLB-H-US-CFTC-FCM-DCO-CUSTOMER-FUNDS-INVESTMENTS-REG-1-25-2024-Q001-Opus47]. RegLegBrief AI Hallucination Research. https://reglegbrief.com/regulators/j3/us/cftc/fcm-dco-customer-funds-investments-reg-1-25-2024/whitepaper/finding/US-CFTC-US-001-FCM-DCO-CUSTOMER-FUNDS-INVESTMENTS-REG-1-25-2024-v1-001--opus-47-websearch/
Bluebook / OSCOLA (US + UK legal) Download 
RegLeg Specialist Panel, Finding on 'Q001 Probe' for Claude Opus 4.7 with web search ON [RLB-H-US-CFTC-FCM-DCO-CUSTOMER-FUNDS-INVESTMENTS-REG-1-25-2024-Q001-Opus47], RegLegBrief AI Hallucination Research (June 04, 2026), https://reglegbrief.com/regulators/j3/us/cftc/fcm-dco-customer-funds-investments-reg-1-25-2024/whitepaper/finding/US-CFTC-US-001-FCM-DCO-CUSTOMER-FUNDS-INVESTMENTS-REG-1-25-2024-v1-001--opus-47-websearch/.
BibTeX Download 
@misc{reglegbrief_RLB_H_US_CFTC_FCM_DCO_CUSTOMER_FUNDS_INVESTMENTS_REG_1_25_2024_Q001_Opus47,
  author    = {RegLeg Specialist Panel},
  title     = {Finding on 'Q001 Probe' for Claude Opus 4.7 with web search ON},
  year      = {2026},
  publisher = {RegLegBrief AI Hallucination Research},
  note      = {Hallucination finding Citation ID: RLB-H-US-CFTC-FCM-DCO-CUSTOMER-FUNDS-INVESTMENTS-REG-1-25-2024-Q001-Opus47},
  url       = {https://reglegbrief.com/regulators/j3/us/cftc/fcm-dco-customer-funds-investments-reg-1-25-2024/whitepaper/finding/US-CFTC-US-001-FCM-DCO-CUSTOMER-FUNDS-INVESTMENTS-REG-1-25-2024-v1-001--opus-47-websearch/}
}
← Back to case study summary Case study detail →
About Citation IDs →