The Source Question
Most businesses assume AI systems pull from some opaque, inaccessible database of internet data. The reality is more specific and more actionable. AI systems draw from identifiable sources, and understanding those sources tells you exactly where to invest your GEO efforts.
How ChatGPT Sources Local Business Data
ChatGPT is the largest AI search engine by market share. When it recommends a local business, it draws primarily from third-party platforms — Yelp, TripAdvisor, Foursquare, the BBB, and similar directories. Research on AI citation patterns has found that nearly half of ChatGPT's local business citations come from these third-party sources.
The most important thing to understand about ChatGPT's data sources: it cannot access Google reviews. Google's review ecosystem is a walled garden. ChatGPT has no access to Google Business Profile reviews. A business with thousands of Google reviews but no presence on Yelp or the BBB is largely invisible to ChatGPT.
ChatGPT also draws from Bing's search index. Your Bing Places listing and your website's Bing indexing are part of the data pipeline into ChatGPT recommendations.
How Gemini Sources Local Business Data
Gemini is Google's AI system, and it has access to Google's infrastructure. It draws from Google Business Profiles, Google Maps data, and the full Google search index. It also draws heavily from brand-owned websites — more than any other major AI system.
This means Gemini rewards businesses that invest in their own websites. Detailed service pages, accurate LocalBusiness schema, FAQ sections, and current content all feed directly into Gemini's recommendation engine.
How Perplexity Sources Local Business Data
Perplexity positions itself as an answer engine and cites sources inline. It favors niche, industry-specific directories over general platforms. For healthcare queries, it draws heavily from Zocdoc and Healthgrades. For home services, from Angi and Houzz. For legal services, from Avvo and FindLaw.
Perplexity also draws from academic papers, industry reports, and specialized publications. Content that contains citations and data is more likely to be cited by Perplexity than content that does not.
The Strategic Implication
The source differences between AI systems mean that a single-platform strategy is insufficient. A business that has concentrated all its effort on Google reviews is well-positioned for Gemini but largely invisible to ChatGPT. A business that has only claimed its Yelp profile is missing the Gemini and Perplexity channels.
A complete GEO strategy addresses all three major AI systems by building presence on the sources each one trusts. This means distributing review collection across Google, Yelp, and industry-specific platforms, and maintaining an accurate, well-structured website that Gemini can cite directly.
The 86% Insight
Research on AI citation patterns has found that the overwhelming majority of what AI systems cite when recommending businesses is content that businesses directly control: their own websites, their directory listings, and their review profiles. This is not mysterious or inaccessible data. It is content you create and manage.
The implication is empowering: you already control most of what AI systems read about your business. The work of GEO is making sure that content is accurate, consistent, specific, and present on the right platforms.