AI Labs · updated 2026-06-04 · methodology v2.1

Finding on 'Q002 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-Q002-Opus47

What the RLB Specialist Panel found

Finding on 'Q002 Probe' for Claude Opus 4.7 with web search ON

Question (paraphrased to protect IP): Under the 2024 Regulation 1.25 amendments, what dollar-weighted average maturity standard applies to the overall portfolio of customer segregated funds, and which investment types are excluded from that calculation?
AI's response: "the dollar-weighted average time-to-maturity of the portfolio of US government securities held in segregation is limited to 24 months, computed in a manner consistent with SEC Rule 2a-7's WAM methodology"
Regulator's text: The dollar-weighted average of the time-to-maturity of the portfolio may not exceed 24 months. This limit excludes government money market funds, Treasury ETFs, and foreign sovereign debt from the calculation.
Why the AI went wrong: The model reproduced the 24-month ceiling correctly but appended a cross-regulatory methodology reference — SEC Rule 2a-7's WAM computation standard — that does not appear in the CFTC rule. This is a training-side cross-contamination: SEC Rule 2a-7's WAM methodology is a highly prominent concept in money market fund regulation, and the model appears to have grafted it onto the CFTC's maturity limit as a plausible-sounding elaboration. The CFTC rule specifies its own computation scope via exclusions; it does not incorporate 2a-7 by reference.
Cited source(s):

Impact for this audience

This finding implicates cross-regulator concept conflation in the training data. The model correctly retrieved the 24-month WAM ceiling but appended SEC Rule 2a-7's computation methodology as an elaboration — a cross-contamination that occurs when two regulators' frameworks share vocabulary and are trained in close proximity without independence annotations. The error is in the generation layer: the model added a plausible-sounding methodology reference not present in the retrieved CFTC rule text.

References — raw findings (per AI model)

RLB-H-US-CFTC-FCM-DCO-CUSTOMER-FUNDS-INVESTMENTS-REG-1-25-2024-Q002-Opus47 Claude Opus 4.7 (web search on)

This finding also affects

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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-US-CFTC-FCM-DCO-CUSTOMER-FUNDS-INVESTMENTS-REG-1-25-2024-Q002-Opus47

Plain text Download

RegLeg Specialist Panel (2026). "Finding on 'Q002 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-Q002-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-v1-002--opus-47-websearch/

APA 7th edition Download

RegLeg Specialist Panel. (2026). Finding on 'Q002 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-Q002-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-v1-002--opus-47-websearch/

Bluebook / OSCOLA (US + UK legal) Download

RegLeg Specialist Panel, Finding on 'Q002 Probe' for Claude Opus 4.7 with web search ON [RLB-H-US-CFTC-FCM-DCO-CUSTOMER-FUNDS-INVESTMENTS-REG-1-25-2024-Q002-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-v1-002--opus-47-websearch/.

BibTeX Download

@misc{reglegbrief_RLB_H_US_CFTC_FCM_DCO_CUSTOMER_FUNDS_INVESTMENTS_REG_1_25_2024_Q002_Opus47,
  author    = {RegLeg Specialist Panel},
  title     = {Finding on 'Q002 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-Q002-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-v1-002--opus-47-websearch/}
}

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