Glossary·concept

Share of voice (and why most measurements of it are wrong)

The proportion of organic search clicks a brand captures in a category. Computed properly via CTR-weighted ranking position — not mention counts, not raw impressions, not unweighted SERP appearances.

The problem

"Share of voice" is one of the most-claimed and least-defined metrics in marketing. Different tools mean different things:

  • Social listening tools mean share of brand mentions on social — a vanity metric, dominated by complaint volume
  • SEO tools mean share of SERP appearances — useful but ignores that position 1 is worth ~28× position 10
  • PR tools mean share of press mentions — confounded by who pays for distribution

None of these answer the question a CMO actually asks: "What share of consumer attention in this category goes to my brand?"

How Theia measures it

For every keyword in a category:

brand_clicks_k = Σ over URLs owned by brand [ CTR(position_k) ]

Where CTR comes from the position-to-CTR curve for the relevant surface (Google organic, Amazon, AI Overview).

Aggregate across keywords:

SoV_brand = Σ_k ( brand_clicks_k × volume_k )  /  Σ_k ( total_clicks_k × volume_k )

This is click-weighted, volume-weighted, and surface-aware. It is the only definition that maps directly to consumer attention.

What we found in production

BrandNaive SoV (SERP mentions)Click-weighted SoV
Bose (DE headphones)18%7%
Soundcore (DE headphones)22%31%
Canon (UK cameras)24%19%
Sony (UK cameras)21%26%

The pattern: legacy brands look bigger on mention counts than on captured clicks. The challenger brands have figured out the click-weighted game and are eating share invisibly to the dashboards that measure mentions.

Three surfaces, three SoV figures

Modern share of voice is multi-surface:

  1. Google organic SoV — classic, but shrinking as AI Overviews eat clicks above the fold
  2. Amazon SoV — for any brand that sells through Amazon, often more important than Google
  3. AI Overview / LLM citation share — the newest surface; the brand that wins this wins the next decade

A complete SoV measurement spans all three. Single-surface SoV is a 2019 metric.

Why this matters

Wrong SoV measurement leads directly to wrong investment decisions:

  • Brand thinks it's strong → defunds the channel → loses share
  • Brand thinks it's weak → over-invests → wastes budget on saturated terms
  • Brand uses mention-based SoV → optimises for vanity, not clicks

Click-weighted SoV refreshed weekly is the input every brand investment decision should be using.