Nine Search Backends, Nine Different Webs. Why AI Citations Diverge for the Same Query.

Run the same brand-query through ChatGPT, Gemini, Perplexity, Claude, and Grok. Read the citations. The cited URLs will not be the same, the brands featured will not be the same, and in roughly a third of cases one tool will cite your brand confidently while another does not mention it at all. The temptation is to reach for an algorithmic explanation different rerankers, different summarisation styles, different prompt scaffolds. The actual explanation is upstream of all of that. Different tools