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AI Labs · White Paper · OECD · INT · substrate v1

The model added a section that doesn't exist — and both models agreed on it

OECD/LEGAL/0333 has five operative sections. Both Claude Opus 4.7 and Claude Sonnet 4.6 independently fabricated a sixth. Seven findings document structure inflation, qualifier erasure, and invented sub-tiers across the 2025 Merger Review Recommendation.

📅 Published 7 Jun 2026⚙️ Methodology v2.1🏛 OECD/LEGAL/0333 · Merger Review
📰Read the public briefing for this regulation→
The structural fabrication

Five sections became six — independently, by both models

OECD/LEGAL/0333 has five operative sections. Both Claude Opus 4.7 and Claude Sonnet 4.6, each running with web search on, independently produced descriptions of the Recommendation that included a sixth, one drawn from competition law convention rather than from the text itself.

The panel calls this pattern structure inflation: numbered lists, sub-letter enumeration, defined-term framings, internal priority orderings, and fixed dates that the Recommendation simply doesn't contain. Competition lawyers using AI to map the operative structure of a new OECD recommendation for a merger filing strategy brief have a structurally wrong picture of the instrument embedded in their work product.

OECD/LEGAL/0333 — Actual (5 sections)
I. Scope and definitions
II. Notification thresholds
III. Substantive assessment
IV. Remedies
V. International cooperation
Model output — Fabricated (6 sections)
I. Scope and definitions
II. Notification thresholds
III. Substantive assessment
IV. Remedies
V. International cooperation
VI. [Fabricated enforcement/review section]
7
Total findings
2
Models independently fabricating
+1
Section invented
5
Actual operative sections
STRUCTURE INFLATION — FINDING PATTERN Section I Section II Section III Section IV Section V ← actual Section I Section II Section III Section IV Section V Section VIFABRICATED ← model
Both models independently generated a sixth section. Neither referred to the same fabricated content, but both added exactly one non-existent section.
Qualifier erasure

How "should consider" becomes "must implement"

Both models also erased qualifiers. The Recommendation uses "should", "may", and "as appropriate" deliberately. In OECD instruments those words carry real legal weight, which in OECD instruments carry specific, weaker deontic force, upgraded to mandatory language in the models' outputs. A competition lawyer briefing a client on what the Recommendation requires of member authorities reads a different instrument from what the OECD actually published.

Full audit hub: OECD-MERGER-REVIEW-RECOMMENDATION-2025 →