Updated: December 26, 2012
Google, Bing and Yahoo cracked down hard on duplicate content starting December 2010. Penalties hit hardest on February 24, 2011 in the Google Panda algorithm update. Bing and Yahoo rankings followed suite.
How To: The SEO Tools and Process to Address Duplicate Content
An SEO services client with which we work has developed multiple websites for different brands, but the client recycled the content. Instead of writing 100% unique text for each website, paragraphs and sometimes whole pages were used universally across multiple websites. They were getting away without noticeable revenue loss, so despite existing duplicate content penalties (though not actual penalties – more accurately wasting crawl budget and possibly dividing link juice) on interior entry pages, the client decided it was not a big enough priority to rewrite all the content … until now.
February search engine algorithm updates penalized entire websites that have pages similar to any other site that the search engine credits as the originator. Even if words are rearranged and the brand name is switched out, the Google algorithm is not fooled. Google chooses one website as the originator and penalizes the others.
In late 2010, various rankings started to slip. On February 24th, clients with duplicate or similar content across different websites saw a total drop off for #1 ranked keyword phrases. Google guidelines for duplicate content indicate that the algorithm perceives these similar pages as “deliberately duplicated across domains in an attempt to manipulate search engine rankings or win more traffic“.
By the way, these guidelines were [initially] updated March 20, 2011, less than a month after the [first] Panda algorithm update.
Systematic Process of Identifying and Addressing Duplicate Pages
If you are intimately familiar with your websites, like this search engine optimization consultant is, you already know which pages are similar and possibly causing duplicate content penalties. If you are an SEO agency taking on a new client with duplicate content issues, leaving it up to you to figure out where the duplicates are within their online properties, then you may need a few SEO tools to help identify possible duplicate pages.
UPDATES: Google Panda Filter Dates
- Panda Update 1.0: Feb. 24, 2011
- Panda Update 2.0: April 11, 2011 (about 7 weeks later)
- Panda Update 2.1: May 10, 2011 (about 4 weeks later)
- Panda Update 2.2: June 16, 2011 (about 5 weeks later)
- Panda Update 2.3: July 23, 2011 (about 5 weeks later)
- Panda Update 2.4: August 12, 2011 (about 3 weeks later)
- Panda Update 2.5: September 28, 2011 (about 7 weeks later)
- Panda Update 2.51: October 9, 2011 (minor filter update about 2 weeks later)
- Panda Update 2.52: October 13, 2011 (minor filter update)
- Panda Update 3.0: October 19, 2011 (3 weeks later)
- Panda Update 3.1: November 18, 2011 (3 weeks later)
- Panda Update 3.2: January 18, 2012 (8 weeks later)
- Panda Update 3.3: February 28, 2012 (refresh to update index 6 weeks later)
- Panda Update 3.4: March 23, 2012 (refresh to update index 3.5 weeks later)
- Panda Update 3.5: April 19, 2012 (refresh to update index 4 weeks later)
- Panda Update 3.6: April 27, 2012 (refresh to update index 8 days later)
- This has become crazy to update. Just check the SEOMoz Google Algorithm Change History.