Google I/O 2026: what the AI Overviews merger means for brand visibility
Google I/O 2026 merged AI Overviews and AI Mode into one AI Search experience on Gemini 3.5 Flash. Ahrefs found only 38% of AI citations now come from top-10 Google pages, down from 76%.
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Stephan Charles
11 min read
May 22, 2026
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Google I/O 2026 (May 19–20) merged AI Overviews and AI Mode into a single AI Search experience, running on Gemini 3.5 Flash for a combined base of 3.5 billion monthly active users. The timing matters. Ahrefs studied 863,000 keywords and 4 million AI Overview URLs and found that only 38% of cited pages also rank in the top 10 for the same query — down from 76% seven months earlier. That gap is not a rounding error. Google organic rank no longer predicts who gets cited inside AI-generated answers. BrandCited measures your actual citation rate across 8 AI engines, including Google AI Overviews, so you can see where you stand today rather than where your SEO dashboard implies you should be.
Run a free BrandCited scan to see your citation rate across 8 engines: brandcited.ai.
What did Google change about AI search at I/O 2026?#
At I/O on <time datetime="2026-05-19">May 19, 2026</time>, Google merged AI Overviews and AI Mode into one continuous experience, powered by Gemini 3.5 Flash as the new global default model. Users can now move from a standard search results page directly into a follow-up AI conversation without navigating to a separate interface. Google calls this AI Search.
The scale numbers from the keynote explain why the change matters for brand visibility. AI Overviews has 2.5 billion monthly active users as of May 2026, per Google's official I/O announcements. AI Mode surpassed 1 billion monthly active users in its first year, with query volume more than doubling every quarter since launch.
Those two numbers together mean the AI-generated layer of Google Search is no longer an experimental feature. It's the primary surface for roughly 2.5 billion people every month. Your brand's citation rate inside AI Overviews is no longer a secondary metric.
Gemini 3.5 Flash is faster than its predecessor and more capable across most benchmarks than Gemini 3.1 Pro, according to BetaNews coverage of the I/O announcements. Google also announced Gemini Omni, a new AI video model, and Gemini Spark, a personal AI agent. All three share the same retrieval and citation infrastructure that determines which brands appear inside AI Search answers.
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How has Google AI Overview citation behavior shifted since the Gemini 3 upgrade?#
Ahrefs tracked 863,000 keywords and 4 million AI Overview URLs and found that only 38% of pages cited in Google AI Overviews also rank in the top 10 for the same query — down from 76% just seven months earlier, as documented in their updated study on AI Overview citations.
The remaining citations split almost evenly between two groups. Pages ranking between positions 11 and 100 account for 31.2% of all citations. Pages that don't appear in the top 100 at all account for 31%. That last figure is the one that breaks the standard mental model: nearly one in three pages cited inside Google AI Overviews doesn't rank anywhere visible in standard search results.
Search Engine Journal covered the Ahrefs findings and noted that the shift coincides with Google's upgrade to Gemini 3 as the global default for AI Overviews on January 27, 2026. BrightEdge analysis places the share of top-10 citations even lower — around 17% — depending on the keyword set and methodology used.
Why did the AI Overview citation pattern change so sharply in 2026?#
Google upgraded AI Overviews to Gemini 3 on <time datetime="2026-01-27">January 27, 2026</time>, and SE Ranking's post-upgrade analysis found that Gemini 3 replaced approximately 42% of the domains previously cited under the earlier model. A new model with different retrieval weights means a different citation pool from day one.
The volume change explains the math. Gemini 3 delivers 32% more source URLs per AI Overview response than its predecessor. When a system cites 32% more sources, the share held by any single ranking tier drops automatically, even if those top-ranked pages still appear. The absolute citation count per top-10 page may be stable while the percentage falls.
5WPR research published on <time datetime="2026-05-04">May 4, 2026</time> documents the broader structural shift: the overlap between top Google ranking pages and AI-cited sources has collapsed from 70% to under 20% across ChatGPT, Claude, Gemini, Perplexity, and Google AI Overviews combined, per their press release on PR Newswire. They also separately identified the 50 websites that now most frequently appear as citation sources across the major AI platforms — a list that does not map cleanly to any standard domain authority ranking.
Which brands are getting cited in AI Overviews if not the top-ranked ones?#
YouTube is the single most-cited domain in Google AI Overviews and accounts for 18.2% of all citations from pages that don't rank in the top 100, according to the Ahrefs dataset. That's a structural advantage tied to Google's ownership of the platform and YouTube content's intrinsic video-rich, answer-dense format.
Outside YouTube, the citation pool draws from sources that share a content structure rather than a domain authority profile. Lily Ray, VP of SEO Strategy at Amsive, found that brands cited inside AI Overviews earn 35% more organic clicks than non-cited competitors in the same search results, per her research covered by Search Engine Land on AI visibility and citations. Citation inclusion drives clicks even when the brand's organic rank is lower than the uncited competitor above it.
The common thread across cited pages isn't domain authority. It's content extractability: short paragraphs, direct-answer opening sentences, complete FAQ schema markup, and specific named entities in the first 100 words. BrandCited's analysis of 10,000 cited passages across 8 AI engines found that 78% of passages cited by AI engines open with a subject-verb-object sentence containing a specific number or a named entity.
What breaks for brands that assumed Google rank equals AI visibility?#
Brands that measure AI visibility by checking their Google rank are measuring the wrong input. The decoupling is now large enough to produce opposite outcomes: a brand can rank #1 for a query and receive zero citations inside the AI Overview above those organic results.
BrandCited's data from 500 onboarded brands shows that 43% of brands with a top-5 Google position score below 30 on BrandCited's AI visibility index. A score below 30 means the brand appears in AI-generated answers on fewer than 30% of the queries BrandCited probes. The rank exists. The citation doesn't.
The specific mechanism that causes this gap is content structure. A page written as a traditional long-form essay, optimized for dwell time, built around keyword density in body text, and without FAQ schema is not structured for AI extraction — even if it ranks at position one. Gemini 3.5 Flash reads for a direct answer in the opening line, machine-readable Q&A in the schema layer, and named entity density in the first paragraph. Gartner projected a 25% decline in organic traffic to commercial sites in 2026 as AI-generated answers absorb query intent that used to resolve as clicks. Brands that miss the AI citation layer lose twice: no click from the organic result, no brand mention in the AI answer above it.
What should you do after the Google I/O 2026 AI search changes?#
Track your AI visibility for free
See how ChatGPT, Claude, Gemini, and 4 other AI platforms mention your brand.
1Run a BrandCited scan at brandcited.ai to get your current citation rate across 8 AI engines, including Google AI Overviews. The scan shows exactly which queries your brand answers and which it misses.
2Audit your schema markup on your top 5 pages. Add Article and FAQPage JSON-LD blocks if they're missing. BrandCited's analysis of 847 brands found that complete schema lifts composite AI visibility scores by 23 points.
3Rewrite H2 opening sentences on key articles. Every H2 section's first sentence needs to answer the heading question directly — specific number or named entity in the first 20 words. That's the format Gemini 3.5 Flash cites.
4Submit restructured pages to Bing Webmaster Tools and Google Search Console for fast reindexing. Perplexity and Copilot can reflect newly structured content within 7 to 21 days.
5Set up monthly monitoring so you see citation shifts before they affect traffic. AI citation patterns move on model upgrade cycles, not on content age. A model swap like the Gemini 3 rollout changed 42% of cited domains overnight.
Google I/O 2026: Google merged AI Overviews and AI Mode into one AI Search experience running on Gemini 3.5 Flash. Three new Gemini models were announced: Flash, Omni, and Spark. (BetaNews, May 20, 2026)
OpenAI personal finance: OpenAI launched ChatGPT for personal finance on May 15, letting US users connect over 12,000 financial institutions for spending analysis and planning. (TechCrunch)
Perplexity Deep Research upgrade: Perplexity upgraded Deep Research to run on Opus 4.5 for Max and Pro users, achieving state-of-the-art performance on leading external benchmarks. (Perplexity changelog)
GPT-5.5 Instant: OpenAI replaced GPT-5.3 Instant with GPT-5.5 Instant as the default ChatGPT model on May 5, reducing hallucination rates in medicine, law, and finance by 52.5%. (TechCrunch)
5WPR Citation Source Index: 5WPR released its AI Platform Citation Source Index identifying the 50 websites that dominate AI platform citations across ChatGPT, Claude, Perplexity, Gemini, and Google AI Overviews. (PR Newswire)
How does BrandCited track your Google AI Overview citation rate?#
BrandCited probes 8 AI engines, including Google AI Overviews, with queries relevant to your brand and category. The scan returns a citation rate per engine, a composite score from 0 to 100, and a list of the specific queries where your brand appears and where it doesn't. If your Google AI Overviews citation rate changed after the I/O 2026 model upgrade, BrandCited's monthly rescan will show you the before-and-after delta. Run the free scan at brandcited.ai — 30 seconds, no signup required.
If you want to see exactly how your brand's citation rate breaks down across Google AI Overviews and the other 7 AI engines BrandCited monitors, the free scan gives you that picture in 30 seconds. Google's model upgrades change citation patterns overnight. BrandCited's monthly monitoring cadence means you find out when your number moves — not three months later when traffic data catches up.
What did Google announce about AI search at I/O 2026?
At Google I/O 2026 (May 19–20), Google merged AI Overviews and AI Mode into a single AI Search experience powered by Gemini 3.5 Flash. AI Overviews has 2.5 billion monthly active users and AI Mode surpassed 1 billion. The merger lets users move from a standard search result into a follow-up AI conversation without leaving the page, per MacRumors' I/O 2026 roundup.
Why do top-ranked Google pages get fewer AI Overview citations than before?
Google upgraded AI Overviews to Gemini 3 on January 27, 2026. SE Ranking found Gemini 3 replaced 42% of previously cited domains and delivers 32% more source URLs per response. A wider source pool spread across more pages reduces the share any single ranking tier holds. Ahrefs tracked 863,000 keywords and found top-10 citations dropped from 76% to 38%.
Can a brand rank #1 on Google but not appear in AI Overviews?
Yes. BrandCited's data from 500 onboarded brands shows 43% of brands with a top-5 Google position score below 30 on BrandCited's AI visibility index. 5WPR research found the overlap between top Google rankings and AI-cited sources collapsed from 70% to under 20% across all major AI platforms.
What content structure does Gemini 3.5 Flash favor for citations?
Gemini 3.5 Flash cites content that answers the search query in the opening sentence, uses specific numbers and named entities in the first 100 words, includes FAQPage schema markup, and keeps paragraph lengths under 80 words. BrandCited's scan data shows content with complete Article and FAQPage schema scores 23 points higher on the AI visibility index than content without it.
How do I check my brand's Google AI Overview citation rate?
BrandCited measures your citation rate across 8 AI engines, including Google AI Overviews. The free scan runs in 30 seconds, shows your AI visibility score from 0 to 100, and lists the specific queries where your brand appears and which it misses. Run it at brandcited.ai.
