Co-Citation and Co-Occurrence – The Next Big Thing in SEO

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Google has experimented with a list of algorithm changes. Over the past couple of years, these changes have of course directly affected the way SEO works. If we talk about more precise terms, we see that keywords, back-links and anchor text are some of the terms that have been very dominant, powerful and effective in the search engine optimization world. However, with constant changes in the Google’s algorithm and ranking system, these weighting of these factors has changed drastically over time.

If you remember after the famous Google Panda and Google Penguin updates, link building was significantly revolutionized by the introduction of new, more pure and reliable methods by Google. Likewise, SEO professionals are now suggesting that anchor text is perhaps diminishing in significance and is now being replaced by co-citation and co-occurrence, as many SEO professionals and analysts believe

What is Co-Citation?


As strange as it may sound, co-citation refers to the process of link building without actual links. Unlike anchor text, where actual links were embedded in words or phrases, co-citation does not necessarily have to involve actual outgoing links to your website or blog.
More precisely, the process of co-citation refers to the similarities found between two webpages, based on a third-party webpage that successfully mentions the first two webpages in a correlation with each other. Based on that co-citation, Google identifies a relation – or link – between those two websites, which is then used as an important search engine-ranking factor.

What is Co-Occurrence?


As these terms are not officially confirmed yet, there is a significant amount of doubt in the proper definition and explanation about co-occurrence. Some SEO professionals have suggested that co-citation and co-occurrence basically refer to the same concept. On the other hand, however, other SEO analysts and professionals, who have a keen eye on every modern SEO development, claim that co-occurrence is a bit different than co-citation.

According to the second group of thinkers, co-occurrence does not associate two sites altogether. Instead, co-occurrence refers to the association of some particular phrases – or more specifically, important keywords – that come in close proximity to each other. This close proximity of important keywords develops an association and relation that are understandable by Google as an important search engine factor.

Although a few citations may not drastically improve your search engine rankings, it will definitely put you on the right direction in terms of improving your website’s search engine optimization. On being associated a lot of times by impartial sources, it has the potential to create a significant positive impact on your website or blog.

Is There Any Evidence to This Theory?

It is important to understand that unless some thorough and detailed confirmation arrives, this is to remain and be known as a mere ‘theory’. However, there has been some evidence that support this theory, although many professionals are still suggesting otherwise.

Rand Fishkin, the famous SEO analyst and owner of SEOmoz, first started to analyze some strange search engine results that prompted him to inquire further and come up with this theory of co-citation and co-occurrence. In his November 2012 presentation of Whiteboard Friday, he predicted that anchor text may be on the downswing and that Google has introduced another factor for ranking websites in the search engine results, more specifically known as co-citation and co-occurrence.

In that presentation video, he mentioned three examples of such odd search engine results that prompted him to come up with this prediction in the first place. These three examples are quoted below in the words of Rand Fishkin:

“For the query “cell phone ratings,” coming in at number four is a web page on without the words “cell phone” or the word “ratings.” Actually, I do think they have the word “rating,” and they might have the word “phone.” But it’s in the text. It’s not even in the title. Really remarkable that they’re ranking so well for such a competitive query.

Number two, “manufacturing directory.” Again, another very competitive phrase, and ThomasNet is ranking number three without mentioning any of these terms, without seeming to try and target that phrase at all.

Number three, “backlink analysis,” where Open Site Explorer, SEOmoz’s own tool ranks number two, and yet not in the title. It’s not anywhere on the page. Neither of these words are anywhere on the page. In the snippet, Google is actually using some text from another article that they found that mentions backlink analysis.”

In these examples, Rand tries to prove out that these websites are ranked for highly competitive keywords and yet the website copy does not reference these keywords anywhere in the title tags or in the content of the page.

Rand Fishkin says that it is because of the process of co-citation and co-occurrence that these websites rank so high for their main keywords.

Referring to the 1st example of Consumer Reports, Rand says although they have not directly targeted the keyword “cell phones”, but on the Internet, you often see the keywords “cell phones” and “Consumer Reports” coming together.

For example: “Cell phones as rated by Consumer Reports.”

Although there isn’t any direct link, Google is successfully able to find an association between these two terms. And if you remember correctly, this is the whole concept of co-citation and co-occurrence – a link without a link.

Why Co-Citation and Co-Occurrence?

Over the past couple of years, people have successfully manipulated anchor text to falsely improve their website’s search engine rankings, but Google has since started penalizing those websites. The whole idea behind Google is to provide its users with the most accurate, useful and valuable information, and in order to keep it that way, it makes constant improvements in its algorithm methods.

Co-Citation, Co-Occurrence and Search Engine Rankings:

Co-citation and co-occurrence are the outputs of the same need. They can only be developed naturally if the content of your website is good enough to be shared and mentioned with others. On a different note, this is one of the most important reasons why Google puts so much emphasis on social media sharing.

I believe that co-citation and co-occurrence is going to play a fundamental role in determining search engine rankings for websites. According to this co-citation and co-occurrence theory, Google is now focusing on analyzing the association and correlation between two websites on the Internet. In short, such natural and impartial co-occurrences are going to be the future basis of search engine rankings for any website.

How to Earn Co-Citation and Co-Occurrence?

The whole idea of introducing co-citation and co-occurrence – in case if there is any – is to create quality content, have genuine presence on the web and be active on the internet. The concept will keep improving day by day, but right now, you can take the following measures to earn more co-citation and co-occurrences for your website or blog:

  • Create quality content that is worthy to be mentioned and shared on the web.
  • Be proactive on the Internet, in forums and discussion boards.
  • Write more on hot, trending topics, so other people give citations to your valuable content.

Final Thoughts:

As some anecdotal and seemingly unorthodox search engine results have shown that co-citation and co-occurrence factors may actually exist, you might have to look further into it to adapt to its rules and requirements. Google may also make an official announcement about it. It is not that SEO is dying, but it is surely being refined and revamped for providing better results to search engine’s users. Co-citation and co-occurrence seem to be the next big thing in an attempt to avoid manipulation of SERPs, or as many will suggest, it is just another attempt to counter over-optimization, which was the very basis of Google Penguin’s introduction.

Haris Bacic
Haris leads the creative and SEO strategy at AdFicient, a PPC company that specializes in pay per click management, search engine optimization, split testing, and... Read Full Bio
Haris Bacic
Haris Bacic

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  • Nick Davidson


    Has anyone any recent proof of this or any other Penguin update working in the UK? I’m watching competitors with a large number of very poor backlinks rising above my website.One line blog comments, spammy site backlinks and yet they still seem to rise in the rankings.


    • Sahil

      Absolutely! In the growing world of ever increasing spammy techniques and sites which leads to spammy or automated link building, mainly to get traction and to outbeat the competition as soon as possible, citations, co-citations and the relevancy of the citation source will definitely beat external links as a major search engine ranking factors & rightly so.

    • Pankaj Giri

      Hi Nick, Yes I have seen a lot of that kind of sites, even they all have website content copied too.. what we need to think about that … that means Google never Harm popular sites ????? only beat New sites ???????????

      • Nick Davidson

        It does seem sometimes that websites in the USA are more likely to be hit for these spammy techniques, thats all I wanted to say. And since I didnt mention it before, thankyou for a very informative post.

  • Mike Weber

    Thanks for this great post. I remember the time about two years ago when I heard about co-citation technique for the first time, Then it wasnt so important to use in, but today in post-penguin and post-panda SEO world I think this should become one of the most important link building techniques.

  • Timothy

    Interesting post. It definitely annoys me when search engine optimization professionals try to use anchor text in a way that does not blend in with the context of the content. I think this algorithm change is a good move by Google, because it will reward businesses who put out high-quality, sharable content. I would definitely like to see some case studies of how local businesses can successfully implement this strategy. A follow-up post that explains how to implement this tactic would definitely be helpful.

  • Loren Baker

    Nice write up but not sure how it’s the next big thing as this has been common practice for SEOs who know what they’re doing for a good while now.

    But, I guess the cat’s now out of the bag 😀

    Thanks again!

  • Shawn Lippert

    I’m going to test this with a new website I’m building for a Local Home Security company out of Phoenix launching next week.
    I think with Authorship and top professionals in their industry adding these techniques in their writing just may work and add value to content with a link pointing to the subject may help in rankings with Social Search Integration into the organic listings.

  • elmanarah

    Co-citation and co-occurance can get success after some time.Open site explorer is free.You have to offer to world anything free or anything really exceptional.

  • Stuart

    There also may be an algorithmic link between search queries and the page ranking. The Thomas Register example makes me think (maybe obviously) that Google is smart at watching a searcher try multiple queries to find what they’re looking for and associating those terms with the site they ultimately choose.

    This could associate a search term (key word) with a site even though that term is not optimized into the page or its links.

  • mary griffith

    There is nothing more annoying then trying to find something on google and it brings up websites that have nothing to do with what you are looking for. Hopefully these systems can help to eliminate this from happening. We want to find the websites and articles with good quality that will come up when we put a search in on google.

  • Yogesh Gautam

    So high quality sharable content is more important than before. We need to improve our link building techniques too. Now, high quality is the key of success. Bye bye spammer!

  • Francis

    Or it could be simply what has been happening for a long time now is that Google is starting to understand what terms are related or mean the same thing and it doesn’t matter in particular whether your site has co-citation or not.

    Variants of the word manufacture appear 10 times in the source code of the Thomasnet example. There will be thousands of links that say “directory” and quite a few that say “manufacturing” or variants of that too in the anchor text (or around it) going to that site. So with a tool bar page rank of 8 (way higher than the accompanying pages on the serp) then, yes, even when you don’t have great optimisation for that term , that site will rank.

    Find me an example where something ranks and there are NO references to the keyword (or variants) in the anchor text or source code and I might believe things have changed significantly. They haven’t. All that google can understand now is that manufacturing/manufacture/remanufacture etc might mean the same thing.

    Many people are winning big from this by buying plural domains right now. E.g. would rank no.2 ‘cos Google now sees plurals as the same and still uses exact domain matching as a key signal. So Google aint that clever yet folks!

    • Haris

      I agree with your last sentence with the emphasis on the word “yet.” Keep in mind that Google is becoming smarter every day and co-citation and co-occurrence could play a much bigger role than it currently does.

      As always, you need to diversify your SEO tactics and not rely on any one method completely as search engines constantly keep changing and evolving.

  • Mariya

    Creating unique and informative content is from always is known the best way to get attention of users. So I am not getting what new in tit by Citation or Co occurance? Well I really want an explanation on it that how I can improve my website ranking without linking my main keywords on web pages.

  • Andri Yarusman

    Google search engine will have ability like human in future … it can learns, matchs patterns and so on. Co-Occurence is something like building brand … we can say, that building brand online can be your rangking signal on Google this year and next