A missing canonical lets a scraper republish the page and claim the original. It is also the first thing checked when two sites carry identical content and one has to be picked.
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How this rule is weighted
- Importance
- 5 / 10
- How much this matters relative to other rules.
- Confidence
- RESEARCH
- Backed by large-sample study or industry research, not a specification.
- Severity
- warning
- How the finding is presented when it fails.
- Scoring
- Counts
- A failure costs points in its category.
Impact is importance multiplied by the confidence tier’s weight — SPECIFICATION 1.0, RESEARCH 0.7, EMERGING 0.3, EXPERIMENTAL 0.1. Two rules backed by the same class of evidence therefore always carry the same weight, which is what makes the score reproducible rather than hand-tuned.
Questions about this rule
- Does TRUST_CANONICAL_SAME_ORIGIN affect my score?
- Yes. It is an importance 5 rule at RESEARCH confidence, so a failure costs 5 × 0.7 points of impact in the Trust & Scam category before that category is normalised to 100.
- What does RESEARCH confidence mean?
- Backed by large-sample study or industry research, not a specification. Confidence is a declared tier rather than a per-rule number, so every rule backed by the same class of evidence carries the same weight - which is what makes the score reproducible instead of hand-tuned.
- How do I check TRUST_CANONICAL_SAME_ORIGIN on my own site?
- Paste your URL into the box above and it runs only this rule, usually in a couple of seconds. It is also included in the Trust & Scam checker and in a full scan.
Tags
- trust
- seo
- duplication
Related Trust & Scam rules
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- Passwords are never submitted in a URLA GET form puts the password in the query string, where it lands in browser history, server access logs, proxy logs and the Referer header sent to every third party on the next page.TRUST_NO_PASSWORD_OVER_GET
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