Most agencies measure rankings. We measure citations.

Share of Answer (SoA) is the percentage of relevant prompts in which a brand is cited inside an AI-generated answer — across ChatGPT, Perplexity, Gemini, and Google AI Overviews.

It’s not a vanity metric. It’s the closest thing we have to “rank” in a world where the answer is the destination.

Why it matters

When a buyer asks ChatGPT “best GEO agency in Spain”, the answer they get does three things:

1. Picks a small set of named brands (usually 3–7).
2. Quotes or paraphrases content from those brands’ sites.
3. Links — sometimes — to a source.

If your brand isn’t in step 1, none of the rest matters.

How we measure it

For every engagement, we run 50 prompts across four models — ChatGPT (GPT-4o + reasoning), Perplexity (default + Pro), Gemini (2.5 Pro), and Google AI Overviews — and log:

• Whether the brand was cited (binary).
• Position in the cited list (ordinal).
• Whether the citation linked to the brand’s own site (boolean).
• Which sources the model cited instead (competitor map).

We then compute SoA as cited / total, weighted by prompt commercial intent.

What good looks like

For a growth-stage B2B brand in a niche category, 30–45% SoA is a strong baseline after 90 days of work. Above 60% usually means you’ve cornered the entity graph for your category.

We re-measure monthly. The delta is the report.