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Mainboard Issuers × Legal — International / Multilateral · Last updated 11 Jun 2026 · Hallucination Register
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Finding#2, Phantom transnational cooperation operative clause; ex-post assessment omitted

RLB Citation ID: RLB-F-INT-OECD-OECD-MERGER-REVIEW-RECOMMENDATION-2025-Q006
AI's failure:Exposed Fabrication Risk for Mainboard Issuers × Legal:Wrong deliverable
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 Mainboard / Premium-Listed Issuers Sector in international jurisdictions working with the Recommendation of the Council on Merger Review (2025 Revision)

An AI tool characterised the 2025 Recommendation as containing 'Transnational Co-operation' as operative section (v) and 'Monitoring' as section (vi), omitting the actual Section V on ex-post assessment and presenting a six-section structure rather than the correct five. For a legal team preparing jurisdictional analysis or merger control training materials for a transaction team, the error is not cosmetic: the firm's internal framework will describe the OECD standard incorrectly to the lawyers relying on it, and will fail to include ex-post assessment as a live operative commitment under the 2025 revision.

When challenged, the AI acknowledged uncertainty rather than correcting to the accurate structure, meaning reliance on a follow-up prompt to self-correct is not a reliable safeguard for this instrument.

References — raw findings (per AI model)
This finding also affects
← Previous finding Finding#1, Invented cross-border cooperation section; Section V dropped
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#2, Phantom transnational cooperation operative clause; ex-post assessment omitted — Mainboard Issuers × 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/mainboard_issuers/legal/finding/INT-OECD-INT-001-OECD-MERGER-REVIEW-RECOMMENDATION-2025-v1-006/
APA 7th edition Download
RegLeg Specialist Panel. (2026). Finding#2, Phantom transnational cooperation operative clause; ex-post assessment omitted [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/mainboard_issuers/legal/finding/INT-OECD-INT-001-OECD-MERGER-REVIEW-RECOMMENDATION-2025-v1-006/
Bluebook / OSCOLA (US + UK legal) Download
RegLeg Specialist Panel, Finding#2, Phantom transnational cooperation operative clause; ex-post assessment omitted [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/mainboard_issuers/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#2, Phantom transnational cooperation operative clause; ex-post assessment omitted},
  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/mainboard_issuers/legal/finding/INT-OECD-INT-001-OECD-MERGER-REVIEW-RECOMMENDATION-2025-v1-006/}
}
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Every finding on this page compares an AI subject's account of the rule against the regulator's verbatim text from the regulator's own portal. Both are linked. Each delta, its root causes, and impact analysis are documented and published with immutable Citation IDs.