Even the most novice SEO student has long since realized that content is king, links (and lots of them) matter, and digital media without external and internal link shares might as well not even come out to play. In recent years, SEO experts have rightly focused on making connections with like-minded content creators, carefully selecting partners that may not be direct competitors, but offer valuable and relevant information. Many less savvy marketers have therefore assumed that links are links, and the more the merrier. As Google algorithms have become all the more sophisticated, it is now readily apparent that all links are not created equal, and the company webmasters keep is key to their own search rankings. Digital creators must now think carefully about who they link to, who in turn links back to them, and – what most currently do not consider – every last link their partners feature too. This concept is currently referred to as co-citation (or co-occurrence in some circles).

Simply put, co-citation in SEO is about the two degrees of separation rule – who you know, and who they know as well. It’s not enough to have a lot of link partners – quality once again trumps quantity.

Co-Citation Breakdown

In academic circles, co-citation is old, but still very relevant, news. If Professor X writes an article about black holes, he has little to crow about if his research never receives citations from other journals. Furthermore, if the black hole article is only cited by small or unheard of institutions with little to no academic clout, Professor X has still not hit a homerun. What he wants, obviously, is for the Harvards and Yales of the world to herald his article as a game changer, and to make relevant and notable citations to his research. That is the academic holy grail of co-citations. In the world of SEO, things work remarkably similar.

In the old days of SEO (going back way over a decade) links reigned supreme. If your content had a bundle of incoming links, rankings increased. But as link share sites starting spamming the digital stratosphere, algorithms caught on and upped the ante, thereby discouraging the horribly annoying trend of websites that simply linked to a gazillion other websites, with no actual content (which equaled an abysmal user experience.)

Then came the emphasis on more classic ranking tactics: keywords, anchor text, and the authority of the incoming and outgoing links. Authority, of course, references the reputation of your content partners. IMDB, as an example, maintains a much higher authority over a link to Frank’s Movie Stuff – which is obviously common sense. The newest factor these days with co-citation, however, revolves around association. It’s no longer enough for you to ensure your links are current, relative and authoritative. You must also be aware of who your partners link to. If you link to Frank’s Movie Stuff, and they link to a plethora of sites with bad SEO reputations, you’ve just damaged your own ranking too. Once again, who you know matters.

What Makes Bad Neighborhoods so Bad?

It’s fairly easy for Google to spot sites that link out to clusters of bad domains. “Bad” domains are defined as sites that have little value to the user, employing spam-like tactics that are simply after traffic and user data, without offering any relevant content or services. Domains like these often create a neighborhood of like-minded links, because it wouldn’t make sense to send a user to a content-rich site in a good neighborhood and spoil the endless loop of profit-making clicks. Therefore, bad domains are almost always a part of bad neighborhoods.

Even if you never link to a spammy blog network, you must take note if one of your content partners does. Search algorithms absolutely employ the old adage of “guilty by association.” So think twice when seeking out external links – make sure any linking domain employs the same high-value tactics that you do, or your ranking will suffer.

It’s a Matter of Semantics

Co-citation is not just about link association; word choice is also imperative. As a result, co-citation is often now referenced as co-occurrence, which incorporates semantic similarity. SEO expert Rand Fishkin explains this beautifully in a November 2012 video about co-occurrence.

He suggests that we consider the query “cell phone ratings”, mentioned on a site that also talks about Consumer Reports, but does not link to ConsumerReports.org – say they simply make the statement: “cell phones ratings as compared to Consumer Reports.” Google doesn’t care the link is missing – its algorithms know to put two and two together.

How does this impact your business? It makes keywords related to your brand that much more critical. If high-authority sites simply make a reference to keywords directly tied to your brand, your ranking can increase. You therefore don’t need partners to link to you. This is a huge, fascinating, and uncharted new SEO trend. We are now seeing sites receiving substantial rankings without the typical telltale signs: anchor text, article keywords and text, title tags, etc. And the reason is co-citation / co-occurrence. This is perhaps the most innovative and exciting new SEO trend in years.

In a Nutshell

Co-citation is admittedly a complex concept, but there are a few considerations to add to your SEO know-how going forward. Here are the key takeaways:

* There are good domain neighborhoods, and not so good ones – stay away from the spammy networks completely. This means you don’t link to them, they don’t link to you, and your content partners follow the same policy.

* Authority rules – link to and from reputable sites that are relevant to your content and business.

* Quality over quantity is still a better formula. You want links, but a lot of bad links do far more damage than a few targeted links.

* Links are not the only cornerstone to SEO success – words matter too. Study keyword trends and tactics carefully as you choose your own brand’s top semantic associations. If partners won’t link to you outright, get them to talk about you with selected keywords – this alone can increase your ranking.