Who defines what an ESG rating measures?

The fact

Since 2 July 2026, ESG rating has been a regulated activity in the Union. Regulation (EU) 2024/3005 of 27 November 2024 subjects providers of environmental, social and governance ratings to authorisation by the European Securities and Markets Authority (ESMA), which becomes their direct supervisor. Providers already established were required to notify their intention to continue their activity before 2 August 2026; those falling under the general regime must submit their application for authorisation before 2 November 2026.

The regime is complete: governance, independence, prevention of conflicts of interest, separation of activities, transparency of methods. Articles 23 and 24 require the publication of the methods, models and principal rating assumptions; Commission Delegated Regulation (EU) 2026/871 of 21 April 2026, published in the Official Journal on 28 July 2026 and applicable since 2 July, specifies their elements down to the version number of the method.

The Union has thus decided that this activity deserved a supervisor. That point is no longer in dispute. The point that deserves to be examined lies inside the regime.

Article 28

The chapter of the regulation that organises supervision opens with a prohibition. Article 28 provides that, in the exercise of their functions under the regulation, ESMA, the Commission and the public authorities of the Member States shall not interfere with the content of ESG ratings or with the methods that produce them.

Before the regulation, the authors' mastery of the criteria was a fact: the methods belonged to those who produced them, because no one had undertaken to take hold of them. Since 2 July 2026, that mastery is a status. The legislator did not abstain: it wrote its abstention into the text. The frontier between what the public authority supervises and what it forbids itself to intervene upon is no longer a silence; it is a provision.

The distinction matters. A gap gets filled: interpretation, case law, revision. An express renunciation gets respected. By placing non-interference at the head of the chapter devoted to supervision, the regulation does not limit the supervisor by omission: it defines supervision as a competence that stops at the threshold of content.

Publication is not deliberation

The regulation requires that methods be published, rigorous, systematic, continuous and capable of justification. Nowhere does it require that they proceed from a deliberation.

The transparency organised by Articles 23 and 24 bears on the conditions of production of the rating: what the method retains, how it is revised, what data it mobilises, what limits it acknowledges. It does not bear on the legitimacy of the criteria retained. Organising information about a standard is not organising the discussion that establishes it.

The consequence is observable: two providers may examine the same company and reach different assessments, each in perfect compliance. The producer's compliance says nothing about the content of the measure. The regulation assumes as much: its recitals state that the diversity of methods is a property of the rating market, and that it is for providers to determine their own.

An authority without a public author

It remains to measure what this arrangement institutes.

An ESG rating is not one opinion among others. It enters investment decisions, capital allocations, risk policies, comparisons between companies; it conditions access to financing. It sets a norm in fact, without being a norm in law.

The regulation reinforces that de facto authority. Authorisation, supervision and transparency confer an institutional guarantee on the rating: a rating produced within the regulated framework benefits from the confidence that framework organises. And in the same movement, the only actor that could deliberate the criteria, the public authority, has tied its own hands by regulation.

The result is a singular legal object: an assessment whose authority is publicly guaranteed and whose criteria remain privately determined. The question "who defines what an ESG rating measures?" now has an answer in law: its producer, and its producer alone. This is no longer a market observation; it is the state of Union law.

The power of qualification, here, is not missing: it is located. And it is located outside public deliberation, by public deliberation itself.

Missing qualification, reserved qualification

The Union's first space regulation, under negotiation, shows a qualification on which everything depends and which the text does not examine. The regulation on ESG ratings shows the other modality: a qualification the text examines in order to reserve it expressly to its producer. Missing qualification, reserved qualification: in both cases, the decision plays out in a place the rule does not govern.

For European financial institutions, issuers and investors, the conclusion is not that ESG ratings would be suspect. It is that their measure has an author, that this author is now designated by law, and that the question of the criteria through which the European economy learns to see itself will receive no answer from the supervisor.

Europe guarantees the authority of the rating. It has renounced, in writing, the deliberation of its measure.

Paris, September 2026

Sources · Regulation (EU) 2024/3005 of the European Parliament and of the Council of 27 November 2024 (OJEU L, 12 December 2024), applicable since 2 July 2026 · Articles 23, 24, 25 and 28 · Commission Delegated Regulation (EU) 2026/871 of 21 April 2026 (OJEU, 28 July 2026), applicable since 2 July 2026 · ESMA statement of 1 July 2026 on the transitional period.