The CMA Made Google Show Its UK Search Data

For two years the argument about AI Overviews and publisher traffic has been stuck in the same place. Publishers produce data showing steep declines. Google says the data is flawed and clicks are stable. Nobody can check, because the only party holding auditable numbers has not published them.

That stalemate now has an end date, and it was set by a competition regulator rather than a copyright court. The mechanism is worth understanding even if you never read a regulatory decision, because it changes what British search reporting will contain and it changes what publishers can refuse.

Strategic Market Status, and what it actually is

On 10 October 2025 the Competition and Markets Authority issued a 156-page final decision designating Google as having Strategic Market Status in the provision of general search and search advertising services. This was the first major implementation of the UK's regime under the Digital Markets, Competition and Consumers Act 2024, following an investigation that gathered evidence from Google, more than 80 market participants, and 34 consultation responses.

Three criteria have to be met for the designation. Turnover above £1 billion in the UK or £25 billion globally. Substantial and entrenched market power. And a position of strategic significance. The CMA is required to conduct a forward-looking assessment covering at least five years, and it found Google's market power entrenched enough to persist across that period.

One thing the designation is not, and the CMA says so explicitly: it does not find or assume wrongdoing. It is a status that unlocks a power. Once a firm holds Strategic Market Status, the regulator can impose binding conduct requirements without having to prove illegal behaviour first, which is a materially lower bar than traditional competition enforcement.

The designation runs five years from 10 October 2025 and covers Google Search, search advertising services including Google Ads and SA360, and AI-integrated features. AI Overviews and AI Mode fall explicitly within scope, on the reasoning that they form part of Google's general search infrastructure and appear directly on the results page.

What publishers actually got

The CMA published its final decision on Google Search publisher controls in June 2026. The core of it is a Publisher Conduct Requirement obliging Google to give publishers a control determining whether their content can be used within AI-powered search features, including AI Mode and AI Overviews.

The design is more granular than the headline suggests. Opt-out controls split across two dimensions: whether content is used for grounding in AI features, and whether it is used for AI model fine-tuning. Each operates independently, and each works at domain and page level. In effect it separates content display rights from AI training data rights, which the CMA describes as a world first in binding form, and covers AI Overviews, AI Mode, Gemini and Vertex AI simultaneously.

Crucially it addresses the problem publishers called compelled consent. Allowing Google to crawl your site has been a prerequisite for visibility in search, while the same content is increasingly used to power AI features that reduce your referral traffic. Previously the only way to refuse the second was to sacrifice the first. The conduct requirement decouples them.

Reaction was broadly positive from the Publishers Association and the News Media Association. The Professional Publishers Association raised a specific limitation: publishers will not be able to manage participation across individual AI search products separately, because a single control applies across AI Mode, AI Overviews and other AI-powered features. Granular by dimension and by page, but not by product.

And there is a larger thing publishers did not get, which is worth saying plainly. The conduct requirement gives them control. It does not give them a right to be paid. The intended effect is to strengthen their negotiating position for content deals rather than to establish compensation, which means the standoff moves to a different table rather than ending.

The reporting obligation, which matters more for search work

Buried under the opt-out coverage is the provision that changes day-to-day practice for anyone measuring organic search in Britain.

Google becomes obliged to publish disaggregated engagement metrics, including impressions, click-throughs and click-through rate, through Search Console. Separately reported rather than folded into a single figure.

Understand what that resolves. The entire dispute between Google's stable clicks position and independent researchers' decline findings has rested on the fact that the underlying data was unauditable. Google asserted stability without publishing figures, charts or methodology, and sites could not analyse their own AI Overview performance. Digital Content Next and others called specifically for auditable data broken down by query type, content category and geography. That call now has a regulatory answer.

For publishers it also creates a baseline for future compensation negotiations, since you cannot argue about the value of something you cannot measure. For everyone else running organic search in the UK, it means a class of question that has been unanswerable becomes answerable inside a tool most teams already use.

Date	What happens	Why it matters
10 October 2025	Google designated with Strategic Market Status in general search and search advertising. 156-page final decision. Five-year designation.	Unlocks conduct requirements without proof of illegal behaviour. AI Overviews and AI Mode explicitly in scope.
28 January 2026	Consultation opens on four proposed conduct requirements, with industry roundtables held in February.	First substantive deployment of the Act's conduct requirement powers. 43 businesses and ten trade associations attended the publisher session.
June 2026	Final decision published on the Publisher Conduct Requirement.	Separates content display rights from AI training data rights in binding form, across AI Overviews, AI Mode, Gemini and Vertex AI.
December 2026	Main publisher controls take effect. Google's obligation to publish disaggregated engagement metrics through Search Console begins.	The opt-out becomes usable, and impressions, click-throughs and click-through rate become separately reportable.
March 2027	Page-level grounding controls take effect.	Control moves from whole-domain to individual page, which is what makes selective participation practical rather than all-or-nothing.
Through October 2030	Designation remains in force, subject to review.	Long enough to plan against. This is a regime rather than an incident.

The asymmetry nobody has solved

Here is the structural problem the conduct requirement creates while solving another one.

These obligations attach to Google alone, because only Google holds the designation. Other AI search platforms carry no equivalent duty. A publisher can exercise a well-defined opt-out against AI Overviews and AI Mode, and then discover they have no comparable lever against systems that never came within a regulator's scope.

That produces an uneven content rights landscape at exactly the moment publishers are trying to enforce consistent preferences across platforms. It also creates a peculiar incentive: the most regulated platform becomes the one where your preferences are respected, and the least regulated ones become where your content circulates unchecked.

Regulators in the European Union, Australia and Canada have been watching publisher and platform disputes closely and can now point to the CMA's framework as an operational model. Whether that closes the gap or simply replicates it in more jurisdictions is not yet knowable.

What this does and does not settle

It settles auditability, on a timetable. From December 2026 the claim that clicks are broadly stable and the claim that click-through rates have fallen sharply on affected queries stop being an argument between press releases and become a question answerable from data. That is a genuine shift, and it arrived through competition law rather than through the copyright disputes that have absorbed most of the attention.

It does not settle compensation, and it does not settle platform coverage. Publishers gained a lever and a baseline for negotiation, not a payment. And the lever only works against one platform.

For anyone running organic search in Britain, the practical reading is narrower than the coverage suggests. Two dates to plan around, one new data source to build reporting on, and a regulator's finding that puts the scale of AI search into proportion. The CMA measured AI assistants at 0 to 5% of Google Search query volume on search-grounded queries. Every serious account of 2026 remains a story about coexistence rather than replacement, and it is worth holding that alongside the more dramatic framings.

What does not change is that measuring your own citation footprint remains your own job. A reporting obligation on Google will tell you about Google. It will not tell you what ChatGPT, Perplexity, Gemini as an assistant or Copilot say about you, and no regulator has required anyone to. That gap is the whole reason AI visibility measurement for the UK exists as a discipline separate from organic search reporting, and December 2026 narrows it without closing it.

---

Frequently Asked Questions

What is Strategic Market Status and why does Google have it?

It is a designation under the UK's Digital Markets, Competition and Consumers Act 2024 that lets the Competition and Markets Authority impose binding conduct requirements on a firm without first proving illegal behaviour. Three criteria must be met: turnover above £1 billion in the UK or £25 billion globally, substantial and entrenched market power, and a position of strategic significance. The CMA designated Google on 10 October 2025 in a 156-page final decision covering general search and search advertising, after gathering evidence from Google, more than 80 market participants and 34 consultation responses. The CMA states explicitly that the designation does not find or assume wrongdoing.

Do AI Overviews and AI Mode fall within the designation?

Yes, explicitly. The CMA's reasoning is that they form part of Google's general search infrastructure and appear directly on the search results page. That scope decision is the load-bearing part of the whole framework, because without it the conduct requirements could not have reached AI features at all.

What control do UK publishers actually get?

A control determining whether their content can be used within AI-powered search features including AI Mode and AI Overviews. It splits across two independently operable dimensions, content grounding in AI features and AI model fine-tuning, and works at both domain and page level, covering AI Overviews, AI Mode, Gemini and Vertex AI. The CMA describes it as the first binding measure separating content display rights from AI training data rights. It resolves what publishers called compelled consent, where allowing crawling was a prerequisite for search visibility while the same content powered features reducing their referral traffic.

When do the publisher controls take effect?

Main publisher controls arrive in December 2026, and page-level grounding controls in March 2027. The page-level date is the more consequential one operationally, because it turns opt-out from an all-or-nothing domain decision into selective participation that can be applied per page.

Does the conduct requirement mean Google has to pay publishers?

No, and this is the most significant gap in it. The requirement gives publishers control over whether their content is used, with the intended effect of strengthening their position when negotiating content deals. It does not establish any right to compensation. The standoff between publishers and platforms moves to a different table rather than ending.

What was the criticism from publisher bodies?

The Publishers Association and the News Media Association broadly welcomed the requirements. The Professional Publishers Association raised a specific limitation: publishers cannot manage participation across individual AI search products separately, because a single control applies across AI Mode, AI Overviews and other AI-powered search features. The control is granular by dimension and by page but not by product.

What will Google have to report through Search Console?

Disaggregated engagement metrics including impressions, click-throughs and click-through rate, reported separately rather than folded into a single figure. This is the provision that matters most for anyone measuring organic search, because the entire dispute over whether AI Overviews reduce clicks has rested on the underlying data being unauditable. Google asserted stable and higher-quality clicks without publishing figures, charts or methodology, and sites could not analyse their own AI Overview performance. Digital Content Next and others called for exactly this kind of breakdown.

Do these obligations apply to ChatGPT, Perplexity or other AI search platforms?

No. The obligations attach to Google alone, because only Google holds the designation. Platforms outside it carry no equivalent duty, which creates an uneven landscape: a publisher can exercise a well-defined opt-out against AI Overviews and AI Mode and then find no comparable lever against systems that never came within a regulator's scope. It also produces a perverse incentive, where the most regulated platform becomes the one respecting your preferences.

Why did competition law achieve this rather than copyright law?

Because the bar is lower and the remedy is faster. Under the designation the CMA can impose binding requirements where proportionate for ensuring fair dealing, open choices or trust and transparency, without needing to prove illegal conduct. A copyright claim would require establishing infringement, surviving appeal, and would still not produce a reporting obligation as a remedy. The regulatory route delivered in roughly eight months what litigation has not delivered in two years.

How large is AI search relative to Google Search in the UK?

Small, on the CMA's own finding. In the same decision the regulator found that AI assistants account for only 0 to 5% of Google Search query volume when measured on search-grounded queries. Google holds roughly 91% of UK search across all devices. This makes 2026 a story about redistribution inside a market Google still dominates rather than a transfer of the market elsewhere, and it is worth holding alongside more dramatic framings in either direction.

What should a UK search team do before December 2026?

Four things, none of which require the controls to exist yet. Establish a pre-obligation baseline by recording impressions, clicks and click-through rate by query class now, kept separate rather than merged, so the new data has something to compare against. Form a view on which pages benefit from citation exposure and which are purely being substituted, since page-level control from March 2027 makes that a real decision. Map exposure across platforms beyond Google, because the obligations bind Google only. And stop treating rankings as the primary metric, given that the regulator's own reasoning for bringing AI features into scope is that they occupy the results page above position one.

Will this settle whether AI Overviews reduce traffic?

It will make the question answerable, which is different from settling it. From December 2026, Google's stable clicks position and the independent research showing sharp click-through declines on affected queries stop being an argument between press releases and become a question that can be examined against reported data. What it will not do is tell you anything about non-Google platforms, because no regulator has required disclosure from them. Measuring your own citation footprint across AI systems remains a separate discipline.

---