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Practitioners — Stockbrokers / Trading Reps · updated 2026-06-11
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Finding#2 . Split FS25/2 single-event withdrawal into invented April/August 2025 events

RLB Citation ID: RLB-F-GB-FCA-CONSUMER-DUTY-PS22-9-Q013
AI's failure:Inference Drift Risk for Stockbrokers / Trading Reps:Operational decisions based on a fabricated regulator record
What the RLB Specialist Panel found
For Claude Opus 4.7 (web search on)
Question (paraphrased to protect IP)

Has the FCA withdrawn any pre-Consumer Duty Dear CEO letters following implementation, and if so how many?

RLB's analysis

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.

AI Head's analysis — what weakness in the AI model caused this

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.

The same fabricated timeline appears under a differently framed question (Finding#9), confirming this is a persistent internal model representation rather than a random generation error. Correction pairs targeting FS25/2 directly would be the most efficient remediation.

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
For Claude Sonnet 4.6 (web search on)
Question (paraphrased to protect IP)

Has the FCA withdrawn any pre-Consumer Duty Dear CEO letters following implementation, and if so how many?

RLB's analysis

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.

AI Head's analysis — what weakness in the AI model caused this

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.

The same fabricated timeline appears under a differently framed question (Finding#9), confirming this is a persistent internal model representation rather than a random generation error. Correction pairs targeting FS25/2 directly would be the most efficient remediation.

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 Stockbrokers / Trading Reps in the United Kingdom advising on the Consumer Duty (PS22/9 + PRIN 2A)

Stockbrokers and trading representatives keeping current with FCA supervisory letters need accurate accounts of which letters have been withdrawn. The model's invented April and August 2025 timeline, if relied on in a desk-level compliance briefing, gives the trader the wrong understanding of which supervisory expectations are live.

References — raw findings (per AI model)
This finding also affects
← Previous finding Finding#1 . Fabricated multi-part safe harbour for foreseeable-harm rule
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-F-GB-FCA-CONSUMER-DUTY-PS22-9-Q013
Plain text Download
RegLeg Specialist Panel (2026). "Finding#2 . Split FS25/2 single-event withdrawal into invented April/August 2025 events — Practitioners — Stockbrokers / Trading Reps." Citation ID: RLB-F-GB-FCA-CONSUMER-DUTY-PS22-9-Q013. RegLegBrief AI Hallucination Research, published 2026-06-11. https://reglegbrief.com/regulators/j3/gb/fca/consumer-duty-ps22-9/practitioners/stockbrokers-trading-reps/finding/GB-FCA-GB-001-CONSUMER-DUTY-PS22-9-v1-013/
APA 7th edition Download
RegLeg Specialist Panel. (2026). Finding#2 . Split FS25/2 single-event withdrawal into invented April/August 2025 events [Hallucination finding RLB-F-GB-FCA-CONSUMER-DUTY-PS22-9-Q013]. RegLegBrief AI Hallucination Research. https://reglegbrief.com/regulators/j3/gb/fca/consumer-duty-ps22-9/practitioners/stockbrokers-trading-reps/finding/GB-FCA-GB-001-CONSUMER-DUTY-PS22-9-v1-013/
Bluebook / OSCOLA (US + UK legal) Download
RegLeg Specialist Panel, Finding#2 . Split FS25/2 single-event withdrawal into invented April/August 2025 events [RLB-F-GB-FCA-CONSUMER-DUTY-PS22-9-Q013], RegLegBrief AI Hallucination Research (June 11, 2026), https://reglegbrief.com/regulators/j3/gb/fca/consumer-duty-ps22-9/practitioners/stockbrokers-trading-reps/finding/GB-FCA-GB-001-CONSUMER-DUTY-PS22-9-v1-013/.
BibTeX Download
@misc{reglegbrief_RLB_F_GB_FCA_CONSUMER_DUTY_PS22_9_Q013,
  author    = {RegLeg Specialist Panel},
  title     = {Finding#2 . Split FS25/2 single-event withdrawal into invented April/August 2025 events},
  year      = {2026},
  publisher = {RegLegBrief AI Hallucination Research},
  note      = {Hallucination finding Citation ID: RLB-F-GB-FCA-CONSUMER-DUTY-PS22-9-Q013},
  url       = {https://reglegbrief.com/regulators/j3/gb/fca/consumer-duty-ps22-9/practitioners/stockbrokers-trading-reps/finding/GB-FCA-GB-001-CONSUMER-DUTY-PS22-9-v1-013/}
}
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