What are some of the negative effects of having duplicate content from other sites?

[Charlessipe]

This could include republishing several articles from another site with permission.

[EGOL]

I republish article content from other websites.  This is always done with permission and often the other sites ask me to do it because they have a message that they want to place in front of my visitors.   I value this content because my visitors consume it.

Unfortunately these pages do not perform well in search even though I optimize them so that they do not directly compete for the same keywords as the origins.  Why? There are usually several other sites with the same content. And they compete with each other in the SERPs and share the search traffic.

I incur labor costs in posting the content and acquiring nice images to make it look good on my site.  Sometimes these are not fully recovered because of their reduced traffic.  Also, these pages have a linkjuice flow into them that might be more valuable if sent to other pages.

I view these as costs to serve my visitors and the industry niche of my site.

One other risk is the duplicate content.  Perhaps updates like the Panda update would reduce rankings of sites that contain lots of duplicate content.  I have not seen that yet in my niche.  The quality of the content is some of the highest on the web and the sites that republish it are almost all authoritative.