- Class
- C2 Recommended
- Weight
- 4
- Severity on fail
- major
- Applies to
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Scope and evidence
Evaluated on pages in P with any canonical. The book marks this requirement STANDARD, DOCUMENTED RECOMMENDATION.
Fail conditions
Each condition has a stable code and a reason template. The evaluator fills the placeholders from observed values only; no sentence in a report is generated.
conflicting_canonicals{url} declares {n} different canonical URLs ({list}). Google advises against specifying different URLs as canonical for the same page using different techniques, and RFC 6596 says to specify only one canonical link relation for a resource.
The documented fix
Emit one canonical, from one function, in one place.
Sources, quoted
These are the passages the rule rests on, stored once in the knowledge base and emitted exactly as written. A citation marked for specific conditions appears only on findings with those codes.
“Don't specify different URLs as canonical for the same page using different canonicalization techniques”
[G-CANON] How to specify a canonical URL with rel="canonical" and other methods · General canonicalization best practices · last updated 2026-07-10
https://developers.google.com/search/docs/crawling-indexing/consolidate-duplicate-urls“Specify only one canonical link relation for a resource.”
[RFC6596] RFC 6596: The Canonical Link Relation · 3. The Canonical Link Relation · last updated April 2012
https://www.rfc-editor.org/rfc/rfc6596.html