1,885 pages added structured data. What moved wasn't the markup.
Citations barely shifted — except on the pages whose markup contained real prices and real specifications.
Ahrefs, May 2026 · corroborated independently · June 18, 2026 · 3 min read
Schema markup is the most commonly sold technical deliverable in this market. One agency productises it at $1,997 do-it-yourself and $2,997 done for you, nine schema types, deployed across a whole site.
In May 2026 Ahrefs ran the closest thing this field has to a controlled experiment on it. They identified 1,885 pages that added JSON-LD structured data between August 2025 and March 2026, matched them against 4,000 control pages that didn’t, and compared citations in the thirty days before and after — a difference-in-differences design, which is the right tool for this question.
Google AI Overviews −4.6% small, statistically significant — a decline
Google AI Mode +2.4% indistinguishable from zero
ChatGPT +2.2% indistinguishable from zero
Their verdict: adding schema “produced no major uplift in citations on any platform.” The AI Overviews decline, they say honestly, is unexplained.
A second study arrives at the same place by a different road. Kurt Fischman analysed 730 citations across 1,006 unique pages and 75 commercial queries. A naive analysis appeared to show schema reducing citation odds. Once he controlled for the fact that Google already ranks schema-bearing pages higher, the result was a null result for schema presence. The dominant predictor was position: each rank down the page reduced citation odds by about 24%.
Two independent methods, one conclusion. And Google’s own documentation says the same thing in a sentence: “There’s also no special schema.org structured data that you need to add.”
Now the exception, which is the actually useful part of this article.
Fischman found one category of page that was cited substantially more: pages carrying Product or Review schema with populated concrete attribute fields. Real prices. Real specifications. Actual values in the actual slots.
The markup was not doing the work. The facts inside it were.
That lines up precisely with the strongest controlled study we have. Across 252,000 trials, price disclosure came out as a top-tier gatekeeper — same tier as topical relevance — while structured formatting sat in the weakest tier with an odds-ratio range that dips below 1. And it lines up with a third finding, from hand-coded passage analysis: zero uncited passages contained novel claims or hard numbers. Not few. Zero.
Three methods. One direction. The thing being rewarded is not the container. It is whether there is anything specific inside it.
Ahrefs’ caveats, because they matter. They studied pages already heavily cited — a hundred or more citations — so this may not generalise to obscure pages. Pages that add schema often change several other things at the same time. All schema types were pooled together. The window was thirty days.
So should you add structured data? Yes, and we do — on every engagement.
But for the honest reason, which is not the one it is usually sold with. Structured data helps Google’s ordinary search results, it costs very little once, it is machine-checkable, and it gives you a disciplined place to record the facts about your business in a consistent form. It is good hygiene. It is not an AI visibility lever, and a four-figure price attached to it is being charged for the wrong thing.
The reframe that changes what you’d actually buy. If the effect lives in the facts rather than the format, then the work is not “add schema to 200 pages”. It is: decide what your prices are, what your response times are, what areas you cover, and what is and isn’t included — and then write those down, in the page and in the markup, in the same words.
That is a harder afternoon than running a schema generator. It is also the one with evidence behind it.
