Duplicate Content Penalty SEO article updated March 2014
As an SEO expert who loves to use thin affiliate based content I have fallen foul of Google’s duplicate content filters way too many times, have the duplicate content penalty T-Shirt in multiple colours :(
If you take anything away from the SEO discussion below, it’s NEVER, EVER, EVER add large amounts of duplicate content to important domains.
Thin Affiliate Duplicate Content
Over 5 years ago I had a really nice set of Amazon affiliate stores that used Amazon’s XML datafeed, prior to Google cracking down on thin affiliates for duplicate content: basically content created using the affiliates content with no added value, AKA duplicate content or thin affiliate content, my very easy to make millions of indexed Amazon affiliate product pages (created from duplicate content) went from pulling in 25,000+ unique visitors a day to a fraction of this traffic (probably about 500 visitors when I wrote this, little from Google, today 2014 probably no traffic).
Went from making around $50,000 a year just from those Amazon affiliate stores to a hell of a lot less: made just $117 from Amazon last month (2010), $75 the month before taking into account AdSense income from the stores pages I’m probably making less than $1,500 a year from those pages (2014 update next to nothing now).
Google’s Response to Article Duplicate Content
The same is true of duplicated articles (article content is no different to product content to Google), so if all you do is copy articles from article directories like every second webmaster trying to make easy money online you are highly unlikely to do well in Google long term.
You can get away with some duplicate content, but use too much on a page/site and it will not rank well in Google no matter what you do. That’s not to say duplicate content can’t pull any Google traffic, you might still get some real easy SERPs, but in comparison to what you would get if the content was unique it’s a trickle of traffic. Like I said 25K compared to 500 visitors a day and that’s from about a million indexed pages (Google will still index your duplicated content, but don’t expect a lot of free traffic)!
Google SEO Duplicate Content
My advice is avoid using a significant amount of duplicated content on any page you consider important. I hate to give precise percentages since every page is different, with a small page you can get away with more duplicate content relatively speaking than a large page: if there’s 500 words and 200 are duplicate that’s not that much duplicate content, in comparison if there’s 3,000 words and 1,000 are duplicate (less of a percentage than the first example) that’s a LOT of duplicate content for a page that size. Like wise 200 duplicated words out of 3,000 words isn’t a lot, that could be considered a quote of another page or something which isn’t going to trip any duplicate content filters in Google.
In general I’ve found you can add duplicate content to a site and it not negatively affect your unique content, but if for example you are adding 10 duplicated articles to every 1 unique article, you are pretty much wasting the vast majority of your SEO benefit (from links) on pages that are going to be penalized, basically using duplicate content is a waste of resources.
Duplicate Content and Google SEO 2014
2014 SEO Update: it’s different now, Google does appear to downgrade a site (the entire domain) for having duplicate content, so more duplicate content you have less well your unique content will tend to rank. I see it as a domain trust issue, if all your content is unique Google has no reason to doubt the quality of the content on the site, if a significant amount of content is duplicate it raises questions about the rest of the content. I think of it like a credit score, if you’ve had some bad debts your considered more likely to default on a loan, so your credit score is lowered (your domain is less trusted for having duplicate content).
I don’t know how Google determines how to rank the unique content, might even be the domain isn’t penalized per se, but link benefit (PR) flowing through duplicated content has a dampening factor, similar to how Google disregards the PR/link benefit of some links when they believe they are paid for or acquired to game Google rankings. If the PR is dampened (and I’m not saying it is, just saying it could work this way) more duplicate content Google finds more link benefit that’s wasted.
Duplicate Content SEO Test
I had a website I wasn’t really using, home page PR3. Was a waste to have a website with PR and no content, so I added an automated tool for adding articles from an article directory. So used duplicate article content only.
Over 1,000 articles had been published with many covering niches that are relatively high traffic. Now at PR3 home page I didn’t expect thousands of visitors a day, but if all this content were unique I could expect to see at least 500 visitors a day and probably 1,000.
Actual traffic is more like 10 visitors a day. Update 2014: The domain eventually lost it’s PR3 and never ranked for anything useful, I let the domain expire a while back.
Avoid using duplicate content, I’ve tried all sorts of ways to get past the automated duplicate content penalties, but within a week or two of adding the duplicate content it’s clearly been downgraded in Google SERPs.
There are exceptions, public domain content: no one owns public domain content, when using public domain content it’s NOT duplicate content in the sense of scraping it from another website (stealing it) or using thin content from an affiliate where there is an original source. No one owns public domain content, anyone can use it as they see fit: Google ranks all sites with public domain content equally since there is no original owner. With the correct SEO and marketing campaign a new website can build a new website like Books to Read, add public domain content and gain a Google rank based on the onpage SEO/offpage SEO with no SEO tricks.