In his last videoGoogle's Aurora Morales spoke about duplicate content from the perspective of not only organic search, but also publishers who want to monetize their websites. She began by saying that your site needs to add value, value that is greater than what can be found elsewhere.

Google may limit or disable your Google AdSense ads on your page if your content is duplicated or of low value. The AdSense guidelines Google prohibits placing AdSense ads on "sites whose content is copied or copyrighted" Here are some examples:

• Sites that copy and republish content from other sites without adding original or valuable content
• Sites that copy content from other sites, modify it slightly (e.g., by substituting synonyms or using automated techniques) and republish it
• Sites dedicated to the integration of content such as videos, images or other media from other sites, without substantial added value for the user

Make sure your content is not copied or duplicated from other sites or even from your own website. If you have many similar pages, consider expanding pages that are similar or consolidating them into one page.

Then, on the "organic" side, she explained that sometimes, if not often, duplicate content is not intended to deceive the site owner. Specifically, she explained that URLs sometimes need to be canonicalized. She said this technical duplication "is fine" But she explained that it can cause crawling and indexing problems in some cases. She also explained that these problems can occur with print-friendly pages, or category pages with excerpts. This is all well and good, but Google may not know which page to show in searches. Google recommends using canonicalization to tell Google which page you want to appear in search.

It explains how to report sites that copy your content, including DMCA requests.

Here is the video:

Here is the John Mueller video she references above:

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