DEJAN maps Gemini 4 Hydrogen brand authority across 239,266 brands

DEJAN’s map of Gemini 4 Hydrogen brand authority shows which brands Google’s new model recalls from memory, so the brands it lacks rely on retrieval.

What changed

A map of Gemini 4 Hydrogen brand authority, published by DEJAN on 13 November 2026, ranks 239,266 brands by the authority Google’s new model gives each one when it answers from memory. DEJAN asked the model about brands 52,923 times, using 110.9 million tokens, and extracted 4.4 million links between those brands. Every call went to Gemini 4 Hydrogen through Vertex AI with no search tools.

Parametric memory is the knowledge a model stores in its weights during training and can recall without searching. Dan Petrovic, founder of DEJAN, wrote: “An AI answer draws on two sources: the pages the system retrieves, and what the model already holds from training.” DEJAN’s study measures the second source only.

DEJAN’s authority score runs from 0 to 100, and a brand scores high when many brands lead to it and those brands score high themselves, which is how PageRank scores web pages. Apple, Microsoft and Google lead the overall ranking, and nine of the top ten are technology companies:

Apple scores 100.0, Microsoft 94.3, Google 90.9, Samsung 88.6, Amazon 86.7, Sony 85.2, Meta 84.0, Intel 82.9, AMD 81.9 and Nike 81.0.

Windows ranks 11th with 80.2, yet Gemini 4 Hydrogen never named it in 8,511 requests to name brands. Windows, Android, Office, Azure and Alexa all reach the top 200 because the model lists them near the top when asked about their parent company. DEJAN ran every question on one day, on one model, with search switched off.

Why it happened

Google’s rollout of Gemini 4 Hydrogen in Google Search reached all users on 12 November 2026, and Robby Stein, VP of Product, Google Search, wrote that it is Search’s largest model upgrade so far. DEJAN probed the model the next day because, DEJAN says, Hydrogen became the default model in Google’s AI Mode and handles the hardest AI Overviews questions.

Google’s post says Hydrogen also upgrades query fan-out, in which Search runs simultaneous queries across a question’s subtopics and links more sites than before, so Hydrogen changes both what Google’s model recalls and what Search retrieves.

DEJAN’s first brand probe, the AI Brand Authority Index of 28 March 2026, ran 200,000 recall surveys on Gemini 3 Flash and reached 2,886,212 brands by following links two levels deep. The Hydrogen study adds rankings by industry and so far follows links only one level deep.

What it changes for GEO

Brands that Gemini 4 Hydrogen already holds in memory gain, because the model can name them without retrieving any page. Mid-size brands outside that memory lose the unprompted mention and enter Google’s AI answers only through retrieval, the step described in how Google AI Overviews choose the pages they show. A site blocked to AI crawlers drops out there, and retrieval picks pages titled with the buyer’s question.

Authority in Gemini 4 Hydrogen rises with how many other names point to a brand and how widely, the rule AI engines apply in answers, and a brand’s own claims carry little weight. Windows ranks 11th on Microsoft’s links alone, so a sub-brand inherits its parent’s place. DEJAN’s March index on Gemini 3 Flash, built differently, also put Google, Microsoft and Apple in its top four, so brands the models already know keep their lead.

The overall ranking rewards technology giants, so what matters to a buyer is the brand’s place in its own industry. DEJAN’s data page shows Gemini 4 Hydrogen named 154 brands for Passenger Airlines, so an airline outside those 154 never came up when the model listed its industry. The lead also differs by industry:

With each leader set to 100, Oracle scores 35 against Microsoft in Software and Clorox 37 against Tide in Household Products, while Delta Air Lines scores 97 against American Airlines and Coursera 99 against H&R Block in Diversified Consumer Services.

Gemini 4 Hydrogen fills a brand’s list of ties with owners and sister companies first, then competitors, regional players and adjacent businesses, so a brand named beside another is a competitor only when it sells the same thing. The map covers one Google model, and a brand’s position is judged engine by engine, so ChatGPT and Perplexity need their own reading.

What to do

The head of marketing should have someone look up the brand and its closest rivals on DEJAN’s data page this week, inside the brand’s own industry, and note the rank and the brands Gemini 4 Hydrogen ties to each. If the brand is missing or tied to the wrong industry, the team first checks that robots.txt and the CDN let AI crawlers reach the site, then publishes pages whose titles answer the buyer’s questions.

Over the following months the team earns mentions on the trade and comparison sites that name the brand beside its category, since a model learns about brands from the text it is trained on. The check is how often AI answers to the buyer’s questions name the brand, measured engine by engine with search switched on.