A frontier AI model grafted the EU Commission's structural-remedy sub-hierarchy onto OECD Section IV.3.

A frontier AI subject tested by the RLB Specialist Panel presented the EU Commission's fix-it-first / buyer-pool / crown-jewel ranking as Section IV.3 of the 2025 OECD Merger Review Recommendation, when Section IV.3 states only one preference: structural over behavioural and, within structural, the divestiture of standalone businesses.

The pattern in one line

A frontier AI model tested on the 2025 OECD Merger Review Recommendation grafted the EU Commission's structural-remedy sub-ordering onto Section IV.3 of the Recommendation, producing a legal answer that imports EU practice as OECD content.

How the RLB Specialist Panel tested this

The questions in this cell were prepared by the RLB Specialist Panel based on real, practical AI usage in the workflows that legal teams at telecommunications firms actually use AI for under the 2025 OECD Merger Review Recommendation. Each question targets a specific deliverable type where an AI assistant is plausibly the first draft: an operative-section summary in a client memo, a remedies-hierarchy paragraph in a regulatory-strategy paper, a failing-firm-defence formulation in a transaction-committee briefing, a Council-reporting cadence line in an inter-agency engagement note. The Panel issued each question to two frontier AI subjects with web search active.

The Panel then bound every AI response to verbatim regulator-issued source text held as primary substrate, comparing the model output against the operative OECD Recommendation text and the supporting OECD guideline used to verify cross-references. Only responses where the AI subject was demonstrably wrong against the verbatim regulator-issued source text are published as findings; responses that were substantively correct, or that refused on calibration grounds, are retained internally and not surfaced.

What the models got wrong

Finding: EU merger-control remedy sub-hierarchy grafted onto OECD Section IV.3. The Specialist Panel asked, in application form, what Section IV.3 of the 2025 Recommendation establishes as the hierarchy for acceptable remedies in merger proceedings, and what priority ordering applies within the structural remedies tier. Claude Sonnet 4.6 with web search active answered that, within structural remedies, there is a further internal preference ordering: upfront or 'fix-it-first' divestitures rank highest, divestiture commitments with an approved buyer pool and a trustee mandate as backstop rank second, and 'crown jewel' or ring-fenced asset packages rank third (RLB-H-INT-OECD-OECD-MERGER-REVIEW-RECOMMENDATION-2025-Q002-Sonnet46).

The substrate held by the Panel records Section IV.3 verbatim: 'Prioritise structural remedies over behavioural ones and, for structural remedies, prioritise the divestiture of standalone businesses.' There is one stated preference: structural over behavioural, and within structural the divestiture of standalone businesses. The fix-it-first / buyer-pool / crown-jewel ranking is an EU Commission practice convention that does not appear in the OECD text.

Why this matters for Legal teams at Telecommunications firms

For legal teams at telecommunications firms advising on cross-border merger transactions touching the 2025 OECD Merger Review Recommendation, citation accuracy on the operative architecture, on Section IV.3 remedies hierarchy, and on Section III.11.b failing firm defence is load-bearing in every authority-facing submission, every board memo, and every transactional document. A counterparty or competition authority who identifies a structural inflation, a misattributed sub-hierarchy, or a closed-cumulative-test framing on first reading calls the entire piece of advice into question.

The structural-architecture failure is the most directly visible: a board memo or regulator-facing submission that lists 'international co-operation' or 'monitoring' as operative RECOMMENDS sections is wrong on first reading. The Section IV.3 EU sub-hierarchy import is the most insidious failure, reading as authoritative because the EU framework is real, but presenting EU practice as OECD content imports the wrong normative baseline into the firm's remedy strategy.

The regulator's actual position

One stated preference within structural remedies; no internal sub-ordering. Section IV.3 of the 2025 Recommendation states one preference, verbatim: 'Prioritise structural remedies over behavioural ones and, for structural remedies, prioritise the divestiture of standalone businesses.' That is the complete operative hierarchy for remedies under the OECD instrument. The further internal sub-ordering, fix-it-first divestitures first, approved buyer pools with trustee mandates second, crown jewel or ring-fenced packages third, is an EU Commission merger-control practice convention. It is not OECD text.

A practitioner advising on remedies strategy in an OECD-adherent jurisdiction outside EU practice would be presenting an EU-specific normative baseline as if it were the OECD's stated position.

What this tells us about AI for Legal teams at Telecommunications firms

For legal teams at telecommunications firms working with AI on the 2025 OECD Merger Review Recommendation, the recurring pattern is Misattributed Cross-Jurisdictional Doctrine: the EU Commission's structural-remedy sub-ordering, fix-it-first divestitures, approved-buyer-pool with trustee backstop, crown-jewel packages, is real practice, but it is EU practice, not OECD text. A practitioner advising in an OECD-adherent jurisdiction outside EU practice who relies on the AI characterisation will present the wrong normative baseline in a remedies negotiation or a client memo. The defensive workflow is a citation check against the Section IV.3 verbatim, before any remedies-hierarchy paragraph leaves the drafting stage.

What the RLB Specialist Panel is doing about it

The RLB Specialist Panel is engaging with the AI subjects' developers and with practitioner audiences working under the 2025 OECD Merger Review Recommendation. The Panel maintains an audit register of confirmed hallucinations bound to verbatim regulator-issued source text, surfaces them on the live regulation page and on each audience-specific briefing, and accepts right-of-reply submissions from the AI subjects' developers and from regulator-side reviewers.

For legal teams at telecommunications firms this means the same questions can be re-issued against successor model releases; the bound substrate makes it straightforward to verify whether a specific failure mode has been corrected upstream, or whether the same hallucination is still being produced. Partnership briefings with AI labs are offered against the audit register, not against synthesised demonstrations, so the corrections that matter are evidenced against the operative OECD text rather than against a paraphrase chain.

What Legal teams at Telecommunications firms teams should do

For legal teams at telecommunications firms drawing on AI in workflows that touch the 2025 OECD Merger Review Recommendation, the practical action items are direct:

• Anchor every operative-section reference, every remedies-hierarchy paraphrase, and every failing-firm-defence formulation produced by an AI assistant against the verbatim OECD Recommendation text and the supporting OECD guideline cross-references, before the citation enters a memo, opinion, or regulatory submission.
• Treat any AI-generated structural summary of the 2025 Recommendation as a high-risk paragraph: read the operative RECOMMENDS block directly and confirm that Section V (ex-post assessment) is reflected, and that international co-operation and monitoring are not presented as standalone operative sections.
• When advising on Section IV.3 remedies hierarchy, validate that any structural-remedy sub-ordering presented as OECD content is in fact OECD text and not an EU Commission practice convention imported by paraphrase.
• When advising on the failing firm defence under Section III.11.b, preserve the 'inter alia' signal and the comparative-harm third limb in the deliverable; do not let an AI-drafted closed cumulative test enter the client work product unmodified.
• Maintain a firm-level AI-assist log that records every AI-drafted OECD Recommendation citation entering a client or regulator-facing deliverable, with the verification step explicitly recorded for post-hoc audit.
• Subscribe to the RLB Specialist Panel audit register on the 2025 OECD Merger Review Recommendation to receive notifications when a confirmed AI hallucination is added, withdrawn, or corrected against successor model releases.

Right of Reply

These findings and associated work have been put up in public with a view of the greater good for the development of a safer AI ecosystem. Any party reading this or any finding on reglegbrief.com may contact us and have an unconditional right of reply; the Specialist Panel will publish any factual correction or contextual response alongside the original finding, with no editorial gatekeeping. Researchers, regulators, and compliance teams with questions on methodology or specific findings can reach the Specialist Panel via the same channel.

Source & Methodology Standards

RegLeg Brief is operated by Verdus Technologies Pte. Ltd. (UEN 201616982R), incorporated in Singapore. The RLB Specialist Panel, with an aggregate of over 60 years of public-policy and industry experience, documents only confirmed hallucination findings, under a methodology that requires a verbatim regulator excerpt for every documented claim. All findings, citation IDs, model outputs, regulator excerpts, and methodology notes are open-access.

Primary source verified: OECD/LEGAL/0333, Recommendation of the Council on Merger Review (2025 Revision) · Substrate documents: R1-REGULATION-00001 · OECD portal: oecd.org/legal

Citation IDs referenced:

• RLB-H-INT-OECD-OECD-MERGER-REVIEW-RECOMMENDATION-2025-Q002-Sonnet46