Duplicate Content
What is duplicate content?
Duplicate content is the same or similar content on two different domains. Also on the same domain.
Since search engines like Google value unique and high-quality content extremely highly, duplicate content (also called duplicate content) can become a problem and sometimes result in ranking penalties.

What forms of duplicate content can occur?
A particularly common reason for duplicate content can be unintentional technical, such as:
Internal duplicate content
- if the own website is accessible under several URL'S:
HTTP: http://webseite.de/seite1/ -> https://webseite.de/seite1/
www : if content is reachable with or without www.
Slash: https//website.com/page1 -> https://webseite 1/page/
- Print version: If print-optimized versions exist for one or more pages.
- When different URL parameters are passed for a product by the GET method. This often happens with online stores. Note: the GET method is the right choice compared to the POST method, because it can be read and followed by the crawler.
- If you have a new folder structure and this changes the URL
External Duplicate Content
- Content theft: When someone either publishes the identical content of another website 1:1 in their own website, or reproduces the foreign text similarly.
- Domain transfer: If you change the domain of your own website without a new content. Here you should set 301 redirects. Without these redirects you unintentionally produce duplicate content on different URLs and virtually undermine your own SEO OnPage Optimization.
- If you operate several country versions of your website, use the same content for individual products (a good example here would be DACH websites), you quickly end up with duplicate content.
- Adoption of product description from external producers, suppliers or distributors.
How can I prevent duplicate content?
Internal
For domain accessibility on several ways: with www and without, HTTP and HTTPS, etc. it is best to write a 301 redirect in the .htaccess:
Example code for http/https:
RewriteEngine on
RewriteCond %{HTTP_HOST} ^example.com
RewriteRule ^(.*)$ https://beispiel.de$1 [R=301,L]
A permanent domain move:
RedirectPermanent / https://neue-url.de
For www forward to non-www:
RewriteEngine On
RewriteCond %{HTTP_HOST} ^www.domain\.en$ [NC]
RewriteRule ^(.*)$ http://domain.de/$1 [L,R=301]
For non-www redirect to www:
RewriteEngine On
RewriteCond %{HTTP_HOST} !^www\.domain\.en$ [NC]
RewriteRule ^(.*)$ http://www.domain.de/$1 [L,R=301]
For moving the domain while keeping the page structure from the old domain
RewriteEngine On
RewriteCond %{REQUEST_URI} (.*)
RewriteRule ^(.*)$ http://neue-domain.tld/$1 [L,R=301]
External
In the event of content theft, simply contact the site operator directly and ask them to delete the content.
In case of non-compliance, directly indicate to the search engines that theft has occurred here and that the operator refuses to delete this content despite requests.
- When moving domains, make sure that all pages are forwarded correctly.
- For country versions, you can use the HREFLANG attribute to tell the crawlers that this is the country-specific variant.
Example:
- Website variant for the German-speaking in Germany:
- Website variant for the German speaking in Switzerland:
- Info: Always specify URL in absolute paths.
Always choose your own unique texts for product descriptions
How does Google view duplicate content?
According to John Muller from Google, duplicate content in the internal area is not a negative ranking factor. However, it should be clearly stated that John Muller meant content passages and not entire pages. He further explained that if entire content areas appear on different pages, the algorithm ranks the page that seems most relevant to it. The duplicate content on the other pages is not a problem in itself.
"With that kind of duplicate content it's not so much that there's a negative score associated with it. It's more that, if we find exactly the same information on multiple pages on the web, and someone searches specifically for that piece of information, then we'll try to find the best matching page.
So if you have the same content on multiple pages then we won't show all of these pages. We'll try to pick one of them and show that. So it's not that there's any negative signal associated with that. In a lot of cases that's kind of normal that you have some amount of shared content across some of the pages."
John Muller, Google.
Even if Google doesn't consider internal duplicate content a serious problem, external can lead to major ranking issues. As SEO Agency in Munich we can provide an efficient remedy.