Content is king when it comes to driving organic SEO, but putting forth duplicate information on more than one website could arouse the suspicion of Google filters that will keep a company from being a top result for consumer queries. Whether intentional or accidental, marketers should be aware that similar content on multiple websites is bad for business when it comes to Google rankings.
Google defines duplicate content as "substantive blocks of content within or across domains that either completely match other content or are appreciably similar." The search engine acknowledges this is rarely done with malice, but it can be a deceptive way to manipulate rankings and generate more traffic to a site. In this case, Google has the right to alter search rankings or remove a site completely from its index.
Duplicate content can be an incidental – particularly if a business has a lot of addon domains. Addon domains are generally offered by web hosts as a package deal for companies to register. In a YouTube video on the Google Webmaster Central channel, Matt Cutts, head of Google’s Webspam team, explains that addons are often treated as separate sites, but as such they must be developed as highly unique brand focuses.
Instead, many make the mistake of filling these websites with closely overlapping content. This is a mistake. Cutts says similar content across pages looks "spammy." It sends a signal to Google that "you’re not putting any time or love or attention into developing those domains."
Marketers may avoid SEO death by duplicate content by using add on domains to redirect to a main business website and striving to produce unique, frequently updated content on independent sites.