Why it matters
Said at Search Central Live: several plug-ins emitting the same markup type is one of the most common structured data problems, and the duplicates can make an event detail page look like a list of events and change how Google interprets the page.
How to meet it
Decide which layer owns each type (theme, SEO plug-in, events plug-in, tag manager), disable the others, and merge the output into one @graph per page.
How to test it
The Rich Results Test on one URL per template shows each item once, unless the page really lists several entities.
How Regensbot covers it
Decided from one URL.
An audit reads the response, the headers, the HTML, robots.txt, the sitemaps and the structured data, and the finding shows the evidence it saw.
Sources
Google documents00
No Google document is cited. This requirement was said at Search Central Live and is not documented policy.
Claims in the knowledge base02
- D2-C503UndocumentedWhat is Structured Data and why we need it on the internet.Said on stage
- D2-C504n/aWhat is Structured Data and why we need it on the internet.The author's interpretation
Claim IDs refer to the Search Central Live 2026 knowledge base. The knowledge base (opens in a new tab)
- Undocumented
- Said or shown at the event, not in the documentation.
- n/a
- Nothing to verify: a quotation, framing, opinion or analysis.