What it is
The @id ties structured-data entities together across pages. Unstable or duplicated @ids break those connections and can merge or split entities wrongly. Entity @id not stable/unique. Weakens entity linking across pages/sources. Use stable, unique @id values. Low-medium for entities. Inferred.
Why does unstable/duplicate @id matter for AI search?
Weakens entity linking across pages/sources.
How do you fix it?
Use stable, unique @id values.
How do you find it on your site?
- Review the @id values across your structured data.
- Check they are stable, unique URLs per entity.
- Fix duplicates and ensure each entity has a consistent @id.
- Re-validate the entity graph.
Which ranking and citation factors does it touch?
Stable @ids let Google connect entities correctly across the site. Broken ones fragment or conflate them.
What is the impact?
Low-medium for entities. Inferred.
What is the evidence?
Stable identifiers aid entity understanding. Google Search Central, Structured data general guidelines
Frequently asked questions about unstable/duplicate @id
What does "Unstable/duplicate @id" mean?
Entity @id not stable/unique.
How do you fix unstable/duplicate @id?
Use stable, unique @id values.