Entity authority is the degree to which AI models recognise your brand as a distinct, credible entity with expertise in specific domains. It's not a single score. It's a composite of signals that tell a language model: this is a real thing, it knows what it's talking about, and other credible sources confirm that.
Think of it as the difference between being a name in a database and being a known expert in the room. A brand with high entity authority isn't just indexed - it's understood. The model knows what the brand does, what it's authoritative on, and how it relates to other entities in the same space.
Traditional SEO built authority through backlinks - other sites pointing to you. Entity authority is built through semantic consistency - your claims about your brand being reinforced across multiple credible sources, in structured formats that models can parse, with factual statements that the model can verify against its training data.
The practical consequence is significant. When an AI model generates an answer about a topic in your domain, entity authority determines whether your brand is mentioned, quoted, or recommended. Low entity authority means invisibility. High entity authority means inclusion. There is no middle ground.