The way business buyers choose suppliers is changing faster than most marketing strategies can keep up with.
Esteve Castells, co-founder and co-CEO of LLM Pulse, the Barcelona-based AI visibility measurement platform, set out the evidence at a MarketScale webinar published on Friday.
It is worth noting that LLM Pulse powers MarketScale's own AI Visibility tool, making the host publication a commercial partner of the guest's company.
The scale of the shift
OpenAI said at its DevDay event on September 29 that ChatGPT now reaches 1.2 billion weekly users, up from 400 million in February 2025.
Google's AI Overviews, which place an AI-generated summary above traditional search results, reached 2.5 billion monthly users as of June 2026, Alphabet reported.
Buyers are changing behaviour
A G2 survey of 1,076 B2B software buyers in March 2026 found that 51% now start vendor research in an AI chatbot rather than Google, up from 29% in April 2025.
Sixty-nine percent said they chose a different vendor than originally planned because of AI chatbot guidance, and a third bought from a company they had never previously heard of.
The invisible brand problem
Ranqo, an AI search analytics firm, found that well-known brands appear in 73% of unbranded category prompts, while small brands appear in just 11%.
Across all brand, prompt and engine combinations tracked, 63% returned no mention of the brand at all, Ranqo found.
What AI actually reads
LLM Pulse's data, drawn from thousands of prompts across five AI models, found that 96% of citations shaping a brand's AI appearance came from third-party websites rather than the brand's own pages.
That sits at the high end of independent estimates. Muck Rack, the PR software company, found third-party content accounted for 84% of AI citations across more than 25 million links.
Yext, the digital presence platform, produced a sharply different result, finding that 86% of citations went to sources the brand itself controls, including its own website and its directory listings.
The gap between those figures reflects the type of query. Broad category searches heavily favour third-party content, while transactional searches pull more from a brand's own pages.
Hidden technical barrier
A study by Vercel and MERJ published in December 2024 found that none of the major AI crawlers, including OpenAI's GPTBot and Anthropic's ClaudeBot, render JavaScript when they visit a page.
Content that loads through JavaScript, which covers large portions of many modern websites, is therefore invisible to those tools before the citation question even arises.
What GEO means
Generative engine optimisation (GEO) is the practice of making a brand visible inside AI-generated answers, as distinct from optimising for traditional search rankings.
The term comes from a 2023 paper by researchers at Princeton and IIT Delhi, who found that adding citations, quotations and statistics to content could boost AI visibility by up to 40%.
Ahrefs, the SEO software company, studied 75,000 brands and found that web mentions correlated with AI Overview visibility at 0.664, against just 0.218 for backlink count, suggesting citations now matter more than links.
Volatility factor
Reddit's share of ChatGPT Search citations collapsed from 3.83% to 0.52% in under a month during August 2026, a fall of 86% measured by Promptwatch and reported by Axios.
For brands that had built visibility strategies around Reddit content, the shift arrived without warning, illustrating how quickly AI sourcing can change.
Clicks at stake
Seer Interactive, the digital marketing agency, analysed 5.47 million queries across 53 brands and found that companies cited inside a Google AI Overview earned 120% more organic clicks per impression than those left out.
Ahrefs found that the click-through rate for the top traditional search result falls 58% when an AI Overview appears above it, meaning the reward for inclusion and the penalty for exclusion are both growing.
Money moving in
Profound, a US-based GEO analytics rival to LLM Pulse, raised a $180 million Series D at a $1.8 billion valuation in September 2026, signalling how much institutional money is now chasing this space even as its underlying metrics remain unsettled.
