This finding is a precise defined-term substitution: 'annual income' for 'annual turnover'. This implicates the model's lexical handling of regulatory definitions — specifically, whether its training corpus contained the exact FCA definition or a paraphrase. The fact that web search did not surface the correct term suggests either the retrieval step did not reach the Handbook definition, or the model did not use the retrieved content to override its training inference. A targeted eval checking exact regulatory defined terms (particularly financial thresholds with close synonyms) would catch this class of error.
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.
RegLeg Specialist Panel (2026). "Claude Opus 4.7 with web search — AI Labs." Citation ID: RLB-H-GB-FCA-CONSUMER-DUTY-PS22-9-Q005-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-v1-005--opus-47-websearch/
RegLeg Specialist Panel. (2026). Claude Opus 4.7 with web search [Hallucination finding RLB-H-GB-FCA-CONSUMER-DUTY-PS22-9-Q005-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-v1-005--opus-47-websearch/
RegLeg Specialist Panel, Claude Opus 4.7 with web search [RLB-H-GB-FCA-CONSUMER-DUTY-PS22-9-Q005-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-v1-005--opus-47-websearch/.
@misc{reglegbrief_RLB_H_GB_FCA_CONSUMER_DUTY_PS22_9_Q005_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-Q005-Opus47},
url = {https://reglegbrief.com/regulators/j3/gb/fca/consumer-duty-ps22-9/whitepaper/finding/GB-FCA-GB-001-CONSUMER-DUTY-PS22-9-v1-005--opus-47-websearch/}
}