AI Labs · published 2026-05-26 · methodology v2.1

Claude Opus 4.7 with web search

RLB-H-GB-FCA-CONSUMER-DUTY-PS22-9-Q013-Opus47

What the RLB Specialist Panel found

Finding 13. Claude Opus 4.7 with web search

Question (paraphrased to protect IP): Has the FCA withdrawn any pre-Consumer Duty Dear CEO letters following implementation, and if so how many?
AI's response: > "Around 90+ Dear CEO/portfolio letters were retired in April 2025, with a further tranche of multi-firm and thematic reports retired in August 2025."
Regulator's text: FS25/2 (March 2025): FCA removed more than 90 pre-Consumer Duty Dear CEO letters and cleared over 100 old multi-firm reports.
Why the AI went wrong: The FCA's feedback statement FS25/2 was published in March 2025 and announced the withdrawal of both categories simultaneously. The model re-dated the Dear CEO letter withdrawal to April 2025 and fabricated a separate August 2025 tranche for multi-firm reports that does not exist in the regulator's record. The model appears to have split a single announced action into two sequential events, adding invented dates for each.
Cited source(s):
https://www.fca.org.uk/news/news-stories/fca-simplifies-supervisory-letters — Pretextual
Regulator portal (if any cited link is dud): https://www.fca.org.uk

Impact for this audience

This finding implicates the model's temporal reasoning on regulatory events: it split a single March 2025 announcement (FS25/2) into two events across April and August 2025. This suggests the model had partial training coverage of the FS25/2 publication and filled the gaps with invented dates. The fabricated August 2025 tranche is particularly notable because it post-dates the model's likely training window — this may be the model generating a plausible continuation of a partial knowledge record rather than retrieving a real event.

References — raw findings (per AI model)

RLB-H-GB-FCA-CONSUMER-DUTY-PS22-9-Q013-Opus47 Claude Opus 4.7 (web search on)
RLB-H-GB-FCA-CONSUMER-DUTY-PS22-9-Q013-Sonnet46 Claude Sonnet 4.6 (web search on)

This finding also affects

← Previous finding Finding 3. Claude Opus 4.7 with web search Next finding → Finding 5. Claude Opus 4.7 with web search

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.

Plain text

RegLeg Specialist Panel (2026). "Claude Opus 4.7 with web search — AI Labs." Citation ID: RLB-H-GB-FCA-CONSUMER-DUTY-PS22-9-Q013-Opus47. RegLegBrief AI Hallucination Research, published 2026-05-26. https://reglegbrief.com/regulators/j3/gb/fca/consumer-duty-ps22-9/whitepaper/finding/GB-FCA-GB-001-CONSUMER-DUTY-PS22-9-v1-013--opus-47-websearch/

APA 7th edition

RegLeg Specialist Panel. (2026). Claude Opus 4.7 with web search [Hallucination finding RLB-H-GB-FCA-CONSUMER-DUTY-PS22-9-Q013-Opus47]. RegLegBrief AI Hallucination Research. https://reglegbrief.com/regulators/j3/gb/fca/consumer-duty-ps22-9/whitepaper/finding/GB-FCA-GB-001-CONSUMER-DUTY-PS22-9-v1-013--opus-47-websearch/

Bluebook / OSCOLA (US + UK legal)

RegLeg Specialist Panel, Claude Opus 4.7 with web search [RLB-H-GB-FCA-CONSUMER-DUTY-PS22-9-Q013-Opus47], RegLegBrief AI Hallucination Research (May 26, 2026), https://reglegbrief.com/regulators/j3/gb/fca/consumer-duty-ps22-9/whitepaper/finding/GB-FCA-GB-001-CONSUMER-DUTY-PS22-9-v1-013--opus-47-websearch/.

BibTeX

@misc{reglegbrief_RLB_H_GB_FCA_CONSUMER_DUTY_PS22_9_Q013_Opus47,
  author    = {RegLeg Specialist Panel},
  title     = {Claude Opus 4.7 with web search},
  year      = {2026},
  publisher = {RegLegBrief AI Hallucination Research},
  note      = {Hallucination finding Citation ID: RLB-H-GB-FCA-CONSUMER-DUTY-PS22-9-Q013-Opus47},
  url       = {https://reglegbrief.com/regulators/j3/gb/fca/consumer-duty-ps22-9/whitepaper/finding/GB-FCA-GB-001-CONSUMER-DUTY-PS22-9-v1-013--opus-47-websearch/}
}

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