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Law Firms × Legal — International / Multilateral · Last updated 11 Jun 2026 · Hallucination Register
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Finding#5, Transnational co-operation invented as operative section; Section V dropped

RLB Citation ID: RLB-F-INT-OECD-OECD-MERGER-REVIEW-RECOMMENDATION-2025-Q006
AI's failure:Exposed Fabrication Risk for Law Firms × Legal:Liability / PI exposure
What the RLB Specialist Panel found
Question (paraphrased to protect IP)

What do the primary operative sections of the 2025 OECD Merger Review Recommendation (OECD/LEGAL/0333) address, and what topics were deliberately separated into other OECD instruments rather than included in this Recommendation?

RLB's analysis

On a second, differently-framed question about the same instrument, the model again generated a six-section structure and this time fabricated a specific cross-reference, attributing broader cooperation governance to OECD/LEGAL/0408 (2014), a legal instrument identifier that does not appear in the 2025 Recommendation's text. The response constructed a coherent-sounding inter-instrument division of scope that is consistent with how OECD governance generally works but is not what the 2025 Recommendation states. The repeated structural fabrication across independently posed questions, with web search active, confirms the reconstruction is drawn from training rather than corrected by retrieval.

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

The fabrication of a specific OECD legal instrument identifier (OECD/LEGAL/0408 [2014]) as the basis for a cross-instrument scope division is a citation-generation failure: the model produced a correctly-formatted OECD legal reference that either does not exist or is misattributed. With web search active, the retrieval layer did not flag the fabrication — the generated citation passed the model's internal plausibility check without verification against a retrieved source. This implicates the citation-generation and citation-verification subsystems.

Impact for Legal Teams in Law Firms Sector in international jurisdictions working with the Recommendation of the Council on Merger Review (2025 Revision)

AI described 'Transnational Co-operation' as a standalone fifth operative RECOMMENDS section of OECD/LEGAL/0333 and omitted Section V (ex-post assessment) as a named operative provision, producing a fundamentally wrong characterisation of the Recommendation's operative scope that mirrors the error in Finding 1 but was generated independently.

The convergent nature of this failure across multiple AI tools is the significant signal: it is not a random confabulation but a systematic misrepresentation of this instrument's structure. Any law firm that allows AI-assisted research on this Recommendation into client-facing work without primary-source verification of the operative section list is systematically exposed to producing wrong regulatory characterisations across its merger control practice, with PI consequences that scale with the number of matters on which the error propagates.

References — raw findings (per AI model)
This finding also affects
← Previous finding Finding#4, Failing firm defence conditions presented as closed exhaustive test
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-INT-OECD-OECD-MERGER-REVIEW-RECOMMENDATION-2025-Q006
Plain text Download
RegLeg Specialist Panel (2026). "Finding#5, Transnational co-operation invented as operative section; Section V dropped — Law Firms × Legal — International / Multilateral." Citation ID: RLB-F-INT-OECD-OECD-MERGER-REVIEW-RECOMMENDATION-2025-Q006. RegLegBrief AI Hallucination Research, published 2026-06-11. https://reglegbrief.com/regulators/j1/int/OECD/OECD-MERGER-REVIEW-RECOMMENDATION-2025/sectors/law_firms/legal/finding/INT-OECD-INT-001-OECD-MERGER-REVIEW-RECOMMENDATION-2025-v1-006/
APA 7th edition Download
RegLeg Specialist Panel. (2026). Finding#5, Transnational co-operation invented as operative section; Section V dropped [Hallucination finding RLB-F-INT-OECD-OECD-MERGER-REVIEW-RECOMMENDATION-2025-Q006]. RegLegBrief AI Hallucination Research. https://reglegbrief.com/regulators/j1/int/OECD/OECD-MERGER-REVIEW-RECOMMENDATION-2025/sectors/law_firms/legal/finding/INT-OECD-INT-001-OECD-MERGER-REVIEW-RECOMMENDATION-2025-v1-006/
Bluebook / OSCOLA (US + UK legal) Download
RegLeg Specialist Panel, Finding#5, Transnational co-operation invented as operative section; Section V dropped [RLB-F-INT-OECD-OECD-MERGER-REVIEW-RECOMMENDATION-2025-Q006], RegLegBrief AI Hallucination Research (June 11, 2026), https://reglegbrief.com/regulators/j1/int/OECD/OECD-MERGER-REVIEW-RECOMMENDATION-2025/sectors/law_firms/legal/finding/INT-OECD-INT-001-OECD-MERGER-REVIEW-RECOMMENDATION-2025-v1-006/.
BibTeX Download
@misc{reglegbrief_RLB_F_INT_OECD_OECD_MERGER_REVIEW_RECOMMENDATION_2025_Q006,
  author    = {RegLeg Specialist Panel},
  title     = {Finding#5, Transnational co-operation invented as operative section; Section V dropped},
  year      = {2026},
  publisher = {RegLegBrief AI Hallucination Research},
  note      = {Hallucination finding Citation ID: RLB-F-INT-OECD-OECD-MERGER-REVIEW-RECOMMENDATION-2025-Q006},
  url       = {https://reglegbrief.com/regulators/j1/int/OECD/OECD-MERGER-REVIEW-RECOMMENDATION-2025/sectors/law_firms/legal/finding/INT-OECD-INT-001-OECD-MERGER-REVIEW-RECOMMENDATION-2025-v1-006/}
}
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