Personalization is not considered 'Duplicate Content'

In fact, it can improve your SEO.

Experiences are a great way to create a more personalized experience for your visitors. Customizing your content results in lower bounce rates, higher conversions, more social shares, and a longer time on page. All of these are factors that influence your search rank, so improving them will also positively impact your SERPs ranking.

Personalization is for humans

Personalization is not for bots - it is meant to help individual people with a better user experience. Therefore, we will make sure that your experiences will NOT be indexed by search engines. To prove this, we ran an experiment on several search engines.

Unless deals with bots in the following way

• By default, experiences will not be shown to search engine bots. This prevents duplicate content penalties.
• Ads Bots will have access to experiences, to make sure that the improvements in quality and relevance that you achieve through creating page variations do not go unnoticed.

Preview mode

Before installing the script, your experiences are accessible in preview mode. The preview has a canonical tag that points to the original page. Read the official Google documentation for more information on canonical tags.

Live mode

Bots don't meet "human" targeting conditions. So, instead of displaying your experiences to them, we send bots to your original, unpersonalized page.

Don't be evil - about cloaked content

Like with all other personalization and A/B testing tools, you could abuse Unless to apply black hat tactics such as “cloaking”. Cloaking refers to showing bots and humans drastically different content, just to trick search engines. We strongly discourage you from doing that. Trying to trick search engine bots is never a good idea. As long as your experiences are on topic with your web page and as long as you are using them to improve site experience, you will be safe.

Webmaster

As mentioned before, Unless makes sure that your experiences don't get indexed. If you prefer to take matters into your own hands and take control of which pages get crawled, use your webmaster tools (e.g. Google Search Console). Here you can specify which URLs (and URL parameters) bots are allowed to crawl. For reference, here's the official Google article explaining the process.

Science

If you're still in doubt whether Unless is "safe" from an SEO perspective, take a look at this scientific experiment we ran to proof how Search Engines handle Javascript content and Unless experiences.