- iPullRank found that brands seeded through Gmail appeared more often in Google AI Mode recommendations when Personal Intelligence was enabled.
- The study does not prove that Gmail is a universal ranking factor, but it suggests AI search visibility may become more personal and harder to measure.
Google AI Mode may be moving brand visibility into a more personal part of search: the user’s own inbox.
A new experiment by iPullRank found that brands seeded into Gmail appeared more often in AI Mode recommendations when Google Personal Intelligence was enabled. The strongest observed signal in the test was email, not Google Photos.
The finding is not proof that Gmail is a general Google ranking factor. It also does not apply to every search user by default. Personal Intelligence is opt-in, and the experiment focused on AI Mode with personal context connected.
Still, the study points to an important shift for marketers. AI search visibility may not only depend on websites, links, content and citations. In some cases, it may also be shaped by what a user has received, stored or interacted with inside Google’s own ecosystem.
What iPullRank tested
iPullRank tested whether Google AI Mode recommendations changed when brand signals were added to a Google account connected to Personal Intelligence.
The team used three account types:
- a blank control account
- a blank account connected to Personal Intelligence
- a mature personal Google account with years of existing history
Brand signals were then added through Gmail and Google Photos. The team ran recommendation prompts across categories including coffee machines, banks, running shoes, smartphones, SEO agencies, streaming services and productivity tools.
Across 1,922 AI Mode responses, seeded brands in the Personal Intelligence-connected account became far more likely to appear than in the control account.
According to iPullRank, seeded brand appearance in the Personal Intelligence account rose from 23.9% to 66.8%. In the control account, seeded brand appearance moved from 21.9% to 18.9%.
That is the core result: when Personal Intelligence was enabled, the brands added to personal context appeared much more often in AI Mode recommendations.
Gmail was much stronger than Google Photos
The clearest difference was between Gmail and Google Photos.
Brands seeded through Gmail appeared in 53.6% of relevant responses. Brands seeded through Photos appeared in only 10.5%.
That makes sense. Emails contain clear text. They can connect a brand to a product category, a recommendation, a use case or a reason to choose it. A photo may show a product, but it does not always communicate intent or preference as clearly.
For marketers, this is where the study becomes especially interesting.
Receipts, newsletters, product recommendations, onboarding emails, renewal notices, support messages and comparison content may not only influence what users remember. In a personalized AI search environment, they may also become part of the context AI systems can use later.
That does not mean brands should flood inboxes with manipulative emails. It means useful customer communication may become more important. A good email may not only drive a click today. It may also help create a brand association that can be retrieved later.
Fake brands appeared too
iPullRank also tested fictional brands.
The team created fake brand names and seeded them through Gmail using the same recommendation-style format as the real brand emails. Those fictional brands appeared in 35.7% of relevant responses.
That is one of the more provocative parts of the study, but it needs careful interpretation.
The fake brands had no citation rate because they had no real websites, reviews, product pages or third-party references. They could appear in the recommendation set, but there was no public web layer to support them.
The better takeaway is not that brands can fake their way into AI search. It is that personal context may help a brand enter the answer, while the public web still helps make that brand credible.
Personalization did not replace the web
The study also found that AI Mode still used external sources to support many recommendations.
That matters because it keeps traditional SEO, entity building, product data and digital PR in the picture. Even if personal context influences which brands are considered, Google still appears to rely on the public web to explain, validate or cite many of those brands.
For brands, this points to a layered model of AI search visibility:
- clear owned-site information
- strong product and service pages
- consistent entity signals
- third-party mentions
- reviews and comparisons
- shopping data where relevant
- useful email and CRM communication
The inbox may become one influence point, but it does not replace the web. If anything, it makes the public web more important because AI systems still need sources to ground their recommendations.
Prompt framing changed the results
The study also found that the way a question was asked changed how much personalization appeared.
Prompts that asked AI Mode to recommend a small number of options often showed stronger effects than broad “best right now” prompts. That matters for AI search tracking.
Classic rank tracking is built around relatively stable keywords. AI search does not work that way. A prompt asking for the “best coffee machines” may produce a different brand set than a prompt asking, “If you had to recommend three coffee machines for everyday use, which would you choose?”
That means prompt design is now part of measurement design. One prompt is not enough to understand AI search visibility.
AI search measurement is getting harder
This experiment is important because it challenges one of the simplest assumptions in AI search tracking: that one prompt produces one answer.
If Personal Intelligence becomes more widely used, AI Mode recommendations may vary not only by query, location or device, but by the user’s own Google account history.
A clean tracking account may show one set of brands. A mature account with years of emails, purchases, subscriptions and preferences may show another. A user who recently received several useful emails from a brand may see yet another version.
This also connects to a broader shift in Google Search. At I/O 2026, Google showed how Search is moving further toward an AI agent platform, with AI Mode becoming more capable of handling complex tasks and personalized journeys. We covered that shift in our analysis of how Google is turning Search into an AI agent platform.
That makes AI search measurement closer to audience research.
The question is no longer only:
“Does our brand appear for this prompt?”
It becomes:
“Does our brand appear for this type of user, with this history, in this category, under this prompt framing?”
That is a much harder problem than classic SEO rank tracking.
Why this matters for SEO and marketing teams
For SEO teams, the study reinforces a broader trend: AI search is not only about rankings anymore. It is about recommendation visibility.
Brands need to understand whether they appear in AI-generated answers, how strongly they are recommended, which sources are cited and whether they appear across different user contexts.
For CRM and lifecycle marketing teams, the study adds another possible layer. Email may not only drive clicks, retention or repeat purchases. In personalized AI environments, email could help build brand memory.
For brands, the practical takeaway is simple: be easy to understand everywhere AI might look.
That includes the public web. It may also include the customer’s inbox.
What the study does not prove
The limitations are important.
This was not a test of default AI Mode for every user. It was a test of AI Mode connected to Personal Intelligence. Google says those connections are opt-in and off by default.
The study also does not reveal Google’s internal ranking systems. It only observes outputs.
The account sample was small, the test window was short and the results may vary by category, prompt type and user history.
So the safest conclusion is this: in iPullRank’s experiment, Gmail-seeded brand signals changed AI Mode recommendations when Personal Intelligence was enabled.
That alone is significant.
If Google search becomes more personal through AI Mode, brand visibility may depend on more than pages, links and rankings. It may also depend on whether a brand has already earned a place in the user’s own digital context.
