What does Google say about SEO? /
Quick SEO Quiz

Test your SEO knowledge in 5 questions

Less than a minute. Find out how much you really know about Google search.

🕒 ~1 min 🎯 5 questions

Official statement

Google advises the use of the 'canonical' tag to indicate the original URL of content when it is distributed across multiple sites. This allows Google to recognize the source URL. Meanwhile, the 'nofollow' tag helps to avoid transferring credit from links unduly.
15:51
🎥 Source video

Extracted from a Google Search Central video

⏱ 35:49 💬 EN 📅 28/06/2017 ✂ 6 statements
Watch on YouTube (15:51) →
Other statements from this video 5
  1. 11:27 Les liens sponsorisés doivent-ils vraiment tous être en nofollow ?
  2. 20:54 Les anchor texts optimisés en backlinks : quand Google passe-t-il à l'action contre les infractions ?
  3. 30:56 Faut-il vraiment abandonner les mots-clés généralistes pour des expressions plus précises ?
  4. 31:54 Le rendu JavaScript chez Google : combien de temps avant l'indexation réelle ?
  5. 34:22 Google peut-il vraiment filtrer automatiquement tous les mauvais backlinks ?
📅
Official statement from (8 years ago)
TL;DR

Google recommends using the canonical tag to declare the source URL of syndicated content across multiple domains and the nofollow tag to manage PageRank flow. Effectively, this prevents dilution of your authority and penalties for duplicate content. However, both tags are signals, not absolute directives, and Google may choose to ignore them based on its context assessment.

What you need to understand

Why does Google emphasize these two tags specifically?

When you distribute the same content across multiple sites, Google needs to decide which version to index and which to prioritize in the results. Without clear guidance, it may misjudge and favor a copy over your original. The canonical tag is designed to indicate to it which URL represents the reference version.

The issue is that many partner sites or aggregators do not play by the rules. They republish your content without implementing the canonical link back to your domain, or worse, redirect it to their own URL. In this case, you lose the SEO benefit of your own production.

What is the actual role of nofollow in this equation?

The nofollow tag allows you to control the transfer of PageRank from your site to other domains. If you republish content elsewhere with links to your original site, those links should logically be nofollow to prevent diluting your authority by creating artificial loops.

Google states that this practice avoids 'undue transfer of link credit'. In other words, if you syndicate your content everywhere with dofollow links to yourself, it can resemble a manipulative link scheme. The nofollow tag acts as a safeguard.

Are these tags guidelines or simply recommendations?

This is where it gets tricky. Google treats the canonical tag as a strong signal, but not as an absolute directive. If multiple versions of a piece of content exist and signals are contradictory (powerful backlinks to a copy, better load times, etc.), Google may choose to ignore your canonical.

Nofollow, on the other hand, has become more of a 'hint' than a strict instruction. Google may decide to follow these links if it deems it relevant to the user. In other words, you retain a certain level of control, but not total.

  • The canonical indicates the preferred version, but Google may choose another if other signals are stronger
  • Nofollow limits the transfer of PageRank, but Google may interpret it as just a hint in recent years
  • These tags do not protect against scraping or unauthorized republication of your content
  • A third-party site may ignore your recommendations and implement its own canonical back to itself
  • The combination of both tags is effective only if you control the republishing domains or if your partners adhere to your guidelines

SEO Expert opinion

Does this statement truly reflect what we observe in the field?

Let’s be honest: the canonical works quite well when you control both domains. If you republish your content on a partner site that respects your tags, Google usually consolidates signals toward your original URL. Tests show that in 70-80% of cases, the canonical is respected.

However, issues arise when a third party scrapes your content or when a poorly configured aggregator republishes without the correct canonical tag. In these situations, Google may index the copy rather than the original, especially if the copying domain has higher authority or stronger backlinks. I have seen sites lose their rankings in favor of their own aggregators.

Is nofollow really sufficient to protect against PageRank transfer?

Since Google transformed nofollow into a ‘hint’, the answer is: it depends. In most cases, nofollow effectively prevents the flow of PageRank. However, Google reserves the right to disregard it if the context justifies.

Specifically, if you syndicate content on third-party platforms with nofollow links to your site, you shouldn’t have an issue. However, if you create a network of satellite sites that link to each other with nofollow links, Google may detect this pattern and decide to follow those links to evaluate your footprint. [To check]: Google has never publicly specified the exact criteria that trigger nofollow to be interpreted as an actionable signal.

What are the real risks if these recommendations are not followed?

The main risk is dilution of your SEO authority. If you republish your content everywhere without canonical, Google will spread the signals across multiple URLs instead of focusing them on your main domain. As a result, no version truly performs.

The second risk is penalties for duplicate content. Google does not automatically penalize duplicate content, but if your site is perceived as merely an aggregator or a copy-paste of other sources, it may be demoted. The canonical helps limit this risk by clearly designating the original.

Warning: if you misuse the canonical tag (for example, pointing multiple significantly different pages to a single canonical URL to force indexing), Google may completely disregard your canonical tags across the entire site. This is a sign of bad faith that can degrade your crawl budget.

Practical impact and recommendations

How should you properly implement canonical on distributed content?

First rule: the canonical must point to the absolute original URL, not a relative URL. If you republish an article initially published on yoursite.com/article-123, the tag must contain the full URL with protocol and domain. This avoids any ambiguity for Google.

Second rule: ensure that your syndication partners correctly implement the canonical back to your domain. Many CMS are set up by default to point back to themselves. If you don’t have a clear contractual clause on this point, you risk losing the SEO benefit of your syndicated content.

When should you use nofollow on your own links?

Use the nofollow tag when you republish content on a third-party domain with links to your original site. For example, if you publish an article on Medium or LinkedIn with a link saying ‘Read the full version on our blog’, make that link nofollow. This signals to Google that you are not trying to manipulate PageRank.

However, do not apply nofollow on internal links of your own site, even if some point toward canonicalized pages. Google needs these links to understand your architecture and distribute PageRank internally. Internal nofollow breaks the link structure and harms your SEO.

How can you verify that your canonical tags are being respected by Google?

First method: use the URL Inspection tool in Google Search Console. Enter the URL of the copy (the one republished elsewhere) and check in the ‘Coverage’ section which URL Google considers canonical. If it’s not yours, your tag is being ignored.

Second method: search for quotes of your content in Google. If your URL appears first, the canonical is working. If a copy comes up, you have a canonicalization issue or domain authority problem.

  • Implement the canonical tag with the full absolute URL (protocol + domain + path)
  • Require your syndication partners to contractually add the canonical to your domain
  • Use nofollow on links to your site from syndicated content on third-party domains
  • Regularly check in Search Console which URL Google considers canonical for your duplicate content
  • Monitor sites that republish your content without authorization and request the addition of canonical or removal
  • Never canonicalize significantly different content pages to the same URL
The canonical and nofollow are powerful tools to protect your distributed content, provided you implement them rigorously and control their adherence by your partners. This type of technical optimization, combined with a well-managed syndication strategy, requires sharp expertise. If your site frequently generates republished content or if you collaborate with multiple distribution partners, consulting a specialized SEO agency can help you structure a solid strategy and avoid costly visibility errors.

❓ Frequently Asked Questions

La balise canonical empêche-t-elle Google d'indexer les copies de mon contenu ?
Non, Google peut indexer les copies mais il devrait normalement afficher votre URL d'origine dans les résultats. La canonical indique simplement quelle version privilégier, elle ne bloque pas l'indexation des duplicatas.
Dois-je mettre du nofollow sur tous les liens sortants de mes contenus syndiqués ?
Uniquement sur les liens qui pointent vers votre site d'origine. Les autres liens éditoriaux naturels peuvent rester en dofollow, sauf si vous souhaitez contrôler strictement le flux de PageRank pour des raisons stratégiques.
Que faire si un site republie mon contenu sans ajouter la canonical vers mon domaine ?
Contactez le webmaster pour demander l'ajout de la balise canonical. Si cela échoue et que le site a plus d'autorité que le vôtre, vous pouvez demander la suppression du contenu ou signaler un DMCA si c'est une violation de copyright.
La canonical cross-domain fonctionne-t-elle aussi bien qu'une canonical interne ?
Elle est moins fiable car Google doit faire confiance au domaine tiers. Si ce domaine a une meilleure autorité ou des signaux contradictoires, Google peut ignorer la canonical cross-domain et choisir sa propre version préférée.
Puis-je utiliser la canonical pour fusionner plusieurs pages similaires vers une seule URL ?
Oui, c'est une pratique courante pour consolider les signaux. Mais les pages doivent être réellement similaires ou variantes légères (produits couleur, versions mobile/desktop). Si le contenu est trop différent, Google peut ignorer la balise ou la considérer comme manipulatrice.
🏷 Related Topics
Content Crawl & Indexing AI & SEO Links & Backlinks Domain Name

🎥 From the same video 5

Other SEO insights extracted from this same Google Search Central video · duration 35 min · published on 28/06/2017

🎥 Watch the full video on YouTube →

Related statements

💬 Comments (0)

Be the first to comment.

2000 characters remaining
🔔

Get real-time analysis of the latest Google SEO declarations

Be the first to know every time a new official Google statement drops — with full expert analysis.

No spam. Unsubscribe in one click.