Conventional wisdom says you should build authority off your own site with digital PR, brand mentions, and links from high-authority domains. Increase third-party mentions, increase AI visibility, right? The instinct is correct. But the set of sources an AI leans on changes by topic, which means your off-site authority strategy has to be driven by topics as well. This week: Why AI relies on a different cluster of sources for each topic, and how that reshapes where you invest in authority. Why unfocused off-site authority work burns budget, and how to target it. How to pinpoint the exact sources AI cites for your topic and earn your way into that set. View embedded content AI assembles a unique trusted-source set for every topic AI search engines re-select which sources to trust based on the subject of the query. Ask about invoicing, and it favors one group of sites. Ask about starting a business, and it turns to a largely different group. The data here comes from an anonymized client sample, but it shows the gap is substantial. AI citations follow a topic-specific pattern by source type. For invoicing queries, competitor domains make up 33.5% of what AI cites. For starting-a-business queries, that same source type accounts for just 7%. Same model, two topics, and the mix of sources it prefers almost inverts. This small sample backs up a point I made in “Operationalizing your topic-first SEO strategy”: “You should be employing a topic-based backlink strategy, too. You don’t just want backlinks. You want links that have authority in your target topics…