Ron Jones, a search engine optimization (SEO) expert writing at Search Engine Watch, warns prospective SEO campaigners that identical content posted in multiple locations can spell certain doom for that content’s search ranking.

Search engines, Jones says, work hard to avoid multiple instances of the same content appearing on a given page of search results – although Google at least offers the option to users with its "similar results have been omitted" link displayed below results that have duplicates. The automated processes that search engines use to index web pages will select one from among the duplicates to display, and discard the rest.

Jones also offers suggestions for avoiding issues of duplicate content on sites undergoing search engine optimization (SEO), like the use of canonical tags or new tools that Google has recently released to allow for legitimate content duplication.

Experts say that the strictures against duplicated content are both an effort to provide more relevant search results to users and an indirect effort to preserve the originality of internet content, which is easily copied and reposted.