Microsoft Bing explains how duplicate content can hurt your visibility in AI Search

Did you know that duplicate content can hurt your visibility within AI Search? Fabrice Canel and Krishna Madhavan from Microsoft explained that with AI Search, having duplicate content makes it harder for the systems to understand signals which reduces “the likelihood that the correct version will be selected or summarized.”

This is not too different from how duplicate content or very similar content can cause issues for ranking in traditional search. That is, because AI Search, on Bing and Google, are grounded by the same signals that are used in traditional search – having duplicate content can potentially cause confusion and blur intent signals.

The issue with duplicate content and AI Search. Here are some bullet points from the Bing blog post on why duplicate or very similar content can cause issues with that content showing in AI Search:

• AI search builds on the same signals that support traditional SEO, but adds additional layers, especially in satisfying intent.
• When several pages repeat the same information, those intent signals become harder for AI systems to interpret, reducing the likelihood that the correct version will be selected or summarized.
• When multiple pages cover the same topic with similar wording, structure, and metadata, AI systems cannot easily determine which version aligns best with the user’s intent. This reduces the chances that your preferred page will be chosen as a grounding source.
• LLMs group near-duplicate URLs into a single cluster and then choose one page to represent the set. If the differences between pages are minimal, the model may select a version that is outdated or not the one you intended to highlight. 
• Campaign pages, audience segments, and localized versions can satisfy different intents, but only if those differences are meaningful. When variations reuse the same content, models have fewer signals to match each page with a unique user need. 
• AI systems favor fresh, up-to-date content, but duplicates can slow how quickly changes are reflected. When crawlers revisit duplicate or low-value URLs instead of updated pages, new information may take longer to reach the systems that support AI summaries and comparisons. Clearer intent strengthens AI visibility by helping models understand which version to trust and surface. 

Syndicated content. A lot of people don’t know that syndicated content, content that you may have published on your site but allow others to copy and publish on their own sites, can also cause issues.

Syndicated content, at least as Microsoft defines it, is considered duplicate content. “When your articles are republished on other sites, identical copies can exist across domains, making it harder for search engines and AI systems to identify the original source,” Microsoft wrote.

How do you reduce duplicate content? When it comes to syndicated content, you can try to ask the syndication partner to:

• Add a canonical tag from what they published on their site, to the original version on your site
• You can ask them to rework the content, so it is not too similar
• You can ask them to noindex the content, so search engines don’t see it

Campaign pages. Microsoft also said that “Campaign pages can become duplicate content when multiple versions target the same intent and differ only by minor changes, such as headlines, imagery, or audience messaging.” So you want to make sure to be very careful about your internal site’s page organization and URL structure.

• Select one primary campaign page to collect links and engagement. 
• Use canonical tags on variations that do not represent a distinct search intent
• Only keep separate pages when intent clearly changes, such as seasonal offers, localized pricing, or comparison-focused content. 
• Consolidate or 301 redirect older or redundant campaign pages that no longer serve a unique purpose. 

Localization pages. Yes, localization can also create duplicate content pages. If you have a lot of pages that say the same thing but swap out the city or location, that is too similar to the other pages, which can cause issues. “Localization creates duplicate content when regional or language pages are nearly identical and do not provide meaningful differences for users in each market,” Microsoft wrote.

To fix it, Microsoft suggests:

• Localize with meaningful changes such as terminology, examples, regulations, or product details. 
• Avoid creating multiple pages in the same language that serve the same purpose. 
• Use hreflang to define language and regional targeting

Other technical SEO issues. And yes, technical issues on your site can cause duplicate content. You can have an issue that generates multiple URLs for the same piece of content. Normally, many search engines can handle this automatically but why let the search engine decide, you should control this by ensuring you have only one URL for that one piece of content. URL parameter issues can cause this, HTTP vs. HTTPS variations, upper- and lowercase in the URL, trailing slashes, printer-friendly pages, staging or test sites, and more.

To fix this, Microsoft suggests:

• Use 301 redirects to consolidate variants into a single preferred URL. 
• Apply canonical tags when multiple versions must remain accessible. 
• Enforce consistent URL structures across the site. 
• Prevent staging or archive URLs from being crawled or indexed. 

Why we care. Duplicate content in SEO is not a new topic and it will carry over from traditional search to AI search. Many of you have a lot of experience dealing with duplicate or nearly identical content and how that negatively impacts indexing and ranking.

For more tips and advice, check out the Bing Webmaster blog.