How Google AI Overviews choose sources

Google AI Overviews sit at the top of many search results and try to summarise an answer, with links out to supporting pages. For a brand, the useful question is not “how do I hack the overview.” It is “what has Google actually said about how those links are chosen, and what has independent research observed.”

This article sticks to those two layers: official documentation, then third-party studies. It does not offer a secret ranking recipe, because Google has not published one.

Last updated: 12 November 2026.

Google describes AI Overviews as a way to get to the gist of a complicated topic or question more quickly, and as a jumping-off point to explore links. AI Mode is described as more useful when a question needs further exploration, reasoning or complex comparisons. Both features, Google says, may use a “query fan-out” technique: issuing multiple related searches across subtopics and data sources in order to develop a response, and identifying more supporting web pages while the response is generated. Google also says AI Overviews are only shown when its systems determine that they add something beyond classic Search, and that they often do not trigger. Source: AI Features and Your Website, https://developers.google.com/search/docs/appearance/ai-features

Two practical consequences follow from that description.

First, the set of links under an Overview is not simply “the ten blue links, restyled.” Query fan-out means the system can retrieve pages for related sub-questions, not only for the exact query the user typed. A page that answers a supporting question can appear even if it would not have ranked first for the original phrase.

Second, an Overview is not guaranteed to appear. If you are measuring “how often are we cited in AI Overviews,” you also have to measure how often an Overview appears at all for that query.

Google’s site-owner documentation is unusually direct about what is required, and what is not.

To be eligible to be shown as a supporting link in AI Overviews or AI Mode, a page must be indexed and eligible to be shown in Google Search with a snippet, meeting the ordinary Search technical requirements. There are no additional technical requirements. Meeting those requirements, following policies and following best practices still does not guarantee that Google will crawl, index or serve the page. Indexing and serving are not guaranteed. Source: AI Features and Your Website, https://developers.google.com/search/docs/appearance/ai-features

Google also says there are no additional requirements and no special optimizations necessary to appear in these AI features, and that ordinary SEO best practices still apply: allow crawling, make content findable through internal links, provide a good page experience, keep important content available as text, support it with good images and video where that helps, keep structured data consistent with visible text, and keep Merchant Center or Business Profile information current if you use those products.

You do not, according to the same document, need to create new machine-readable files, “AI text files,” or special markup to appear in AI Overviews or AI Mode. There is no special schema.org type you must add. robots.txt and the usual snippet controls (nosnippet, data-nosnippet, max-snippet, noindex) are the controls Google points site owners to. Google-Extended is discussed separately, as a control for some of Google’s other systems, not as the main switch for Search AI features.

In short: if a page cannot appear as a normal Google Search result with a snippet, it is not eligible to be a supporting link in an Overview. If it can, it is eligible — not selected.

Google has not published the ranking function that chooses which eligible pages become the visible supporting links, or which passages get paraphrased into the overview text. It has not published a list of “trust domains” or a formula that says mentions beat links, or the other way around.

It has said that AI Mode and AI Overviews may use different models and techniques, so the responses and links they show will vary. Treat “I was cited in an Overview” and “I was cited in AI Mode” as different observations.

Anyone selling a guaranteed AI Overview citation is selling something Google itself does not guarantee.

Research can describe patterns. It cannot replace Google’s unpublished selection process, and it cannot prove that a tactic will get you cited.

Ahrefs studied 75,000 brands and measured how strongly various factors correlated with brand mentions in AI Overviews. Branded web mentions had the strongest correlation (0.664). Branded anchors (0.527) and branded search volume (0.392) followed. The three strongest correlations were all off-site factors. Link metrics were weaker: Domain Rating 0.326, referring domains 0.295, backlinks 0.218. Ahrefs emphasises that correlation is not causation, and that even the stronger figures in the study are moderate on a Spearman scale. About 26% of the brands had zero AI Overview mentions. Brands in the top quartile for web mentions averaged 169 AI Overview mentions, more than ten times the next quartile down. Source: An Analysis of AI Overview Brand Visibility Factors, https://ahrefs.com/blog/ai-overview-brand-correlation/

A follow-on Ahrefs analysis compared ChatGPT, AI Mode and AI Overviews. YouTube mentions showed the strongest correlation with AI visibility in that write-up (around 0.737). Branded web mentions remained high across platforms (about 0.66 to 0.71). AI Mode showed stronger correlations with some classic brand signals than ChatGPT or AI Overviews did, including branded web mentions, branded anchors and branded search volume. The assistants also tended to mention many of the same brands. Correlation is still not causation. Source: Top Brand Visibility Factors in ChatGPT, AI Mode, and AI Overviews, https://ahrefs.com/blog/ai-brand-visibility-correlations/

Ahrefs has also reported that AI Overviews are now common on branded searches. In its October 2026 write-up, AI Overviews appeared for 82.91% of US desktop branded searches in the sample dated 29 September, up from 61.3% in July. That is a finding about how often an Overview appears when someone searches a brand name, not a finding about your category queries, and not a finding about offsiteposts.com. Source: AI Overviews Currently Appear for 83% of Branded Searches, https://ahrefs.com/blog/ai-overviews-on-branded-searches/

Slate Research, on 1 October 2026, studied 100 brand-name searches and found that 93 of those brands showed an AI Overview for their own name. Of 652 unique citations, 71% were pages the brand does not own, and 29% pointed to a domain the brand owns. If that pattern holds for your brand, a large share of the sources Google shows next to your own name may be third-party pages. Source: AI Overviews on brand searches, https://slatehq.com/data-studies/ai-overviews-brand-searches

These studies mostly describe branded visibility and off-site mentions. They do not prove that buying a sponsored article will place that article in an Overview, and they do not say Google “prefers” paid placements. Paid placements should be labeled as sponsored, and they are not independent editorial endorsements.

Put the official documentation and the research side by side, and a cautious working model looks like this.

Be eligible. If the page is not indexed, or is blocked from snippets, it is out of the running for a supporting link. That is Google’s rule, not a theory.

Be relevant to the fan-out, not only to the head query. Because the system can issue related searches, a clear page that answers a sub-question — a comparison, a definition, a limitation, a how-it-works explainer — can be more useful than a thin page that repeats the head keyword.

Be citable. Important facts should be in text, not only in an image or a chart. If an Overview is going to paraphrase you, the sentence it needs has to be on the page.

Be present off-site, without over-claiming why. The Ahrefs and Slate work suggests that third-party pages and brand mentions travel with AI visibility, especially for brand-name searches. That is a reason to care about accurate coverage on sites your buyers already read. It is not a reason to promise an Overview citation as a deliverable.

Measure the query set you care about. Count whether an Overview appears, which domains are cited, and whether you are named in the text. Separate branded queries from non-branded category queries. Do not average them into one vanity score.

On your own site, the unglamorous work still matters: crawlability, internal links, clear entities, supportable claims, and pages that deserve to be retrieved for the questions your buyers ask. Google has said the fundamentals of SEO remain the right starting point.

Off your own site, being named in industry articles, listicles, explainers and documentation can add the kind of third-party pages Slate found being cited on branded searches, and the kind of branded web mentions Ahrefs found correlating with Overview visibility. If those pages are sponsored, say so. If a claim cannot be supported, do not publish it.

offsiteposts.com writes and places industry-relevant sponsored content, brand mentions and do-follow links. That work can add third-party pages about a brand to the public web. It does not guarantee AI Overview citations, rankings or traffic. For the mention-versus-link evidence, link to /blog/brand-mentions-vs-backlinks-for-ai-search. For ChatGPT specifically, link to /blog/how-to-get-your-brand-mentioned-in-chatgpt.