By 2 years ago in SEO

Google Moves Towards Continual Crawl Based Link Devaluation

Since November 22nd we have been noticing a new trend with how Google applies algorithms to detect bad links. Earlier in 2012 the focus was very much around major penalisations where a site would literally disappear overnight for lots of keywords but the trend across November, December and January is very much about Google reducing the rankings of certain sites gradually week after week.

We all know that Google has algorithms to detect bad links and the evidence of this was very visible earlier in 2012 but with this latest change Google seems to have developed the capability to continually detect and devalue bad links as part of the standard crawl process, something they were never very good at before. The net result of this is that as Google completes a crawl of a website and the sites linking to it they can devalue those links in real time rather than waiting to roll out a major update such as Penguin or a manual link penalty.

A lot of sites that are suffering are ones that may have been penalised before due to bad links and have not yet removed them all but there are some that are losing ground from a strong position which indicates the latest change is not confined to sites that were hit in the first half of 2012. Google has made it clear that the disavow tool works on a crawl basis whereby all sites submitted will be crawled before the link weight can be cancelled out so there is every reason for them to have merged this capability with the “bad site detection” algorithms they already have in place.

Realistically Google has to move towards a continual process because manual penalisations are not scalable in the long term and they much prefer algorithms over people.

Below are some examples of this trend as shown on Searchmetrics for some of the several hundred sites we monitor recently as part of our competitor analysis. There are lots more that we have seen similar patterns for.

I have only included the past few weeks data rather than the full year because I didn’t want to identify any sites in particular. We would be interested to hear from you in the comments if you have noticed any sites on a gradual slide recently and whether they had previously been penalised or not?

By Patrick Altoft. at 2:59PM on Friday, 18 Jan 2013

Patrick is the Director of Strategy at Branded3 and has spent the last 11 years working on the SEO strategies of some of the UK's largest brands. Patrick’s SEO knowledge and experience is highly regarded by many, and he’s regularly invited to speak at the world’s biggest search conferences and events. Follow Patrick Altoft on Twitter.

comments

  • JC Edwards

    I Have Noticed a distinct change in previously penalised sites that I am monitoring. It is looking more and more like a backlink to page based slap, with traffic and rankings increasing all around the ‘bad’ pages.

    I have also seen the sort of patterns you describe with what I can only describe as gradual link value rot where links are not dropping off but there is a gradual slide.

    Putting the two together it could be assumed that Google is moving towards a more laser guided slap, rather than a ‘throw the whole site out’ slap. Which of course makes sense, as they get to keep the quality content, without having the spammy pages show up.

    I really hope that google do get their act together with regard backlinks as there are a lot of people suffering out there, and nothing they can really do about it due to the fact they don’t know what links are hurting them as WMT doesn’t show them all.

  • http://twitter.com/joshbachynski josh bachynski

    It could also be usage metrics – I have soem data to suggest this may be the bigger culprit – if interested just tweet / email me

  • Mark Griffin

    sometimes i wonder if they won’t be happy until almost all links are harmful to your site

  • http://www.sharanyan.com/ Sharanyan Sharma

    Hi Patrick,
    Great Information, Do you recommend any Link building strategy or any other SEO strategy to get back penalyzed sites ?

  • http://www.brunobabic.com/ Bruno Babic

    Very insightful post, Patrick. Using the Searchmetrics seems to be very useful when doing the competitors analysis. Thanks a lot for making a great effort to compile and share this invaluable information backed up with the graphs.

  • http://www.vinfotech.com/solutions/social-network-design.htm Social Network Design

    I experienced a major drop in ranking for some of my targeted keywords previous week. And as far as I remember, there are no spam links or link exchange. And even the site serves good content to the users and search engines. Perplexed what to do next ??

  • http://www.sharanyan.com/ Sharanyan Sharma

    Another Algorithm rolling out right ?

  • PageRankWorld

    Hmm, they have always been after this, but I just don’t think they are at the necessary level yet for real-time link valuing/devaluing.

  • http://www.seo-theory.com/ Michael Martinez

    I’ll share a working hypothesis I have been keeping to myself (mostly because I haven’t devised a reliable experiment to test it). I suspect that Google is allowing links to pass value for only a (relatively) short period of time and then they have to be re-evaluated. Maybe that has always been the case and they are just getting more efficient at doing this. It feels like something similar to Moore’s Law may have emerged in search engine link valuation, even if that is unintentional.

  • Amir

    Well its going to be more powerful Google SEO With this google moves the serp results gets more clean.

  • Marcus Tarrant

    Has anyone got this sorted yet? I really need help. Bleeding a few k per month as a result and no idea what to do about it!

    • Tim Grice

      On going link devaluation is still happening. There is no way to solve it without disavowing the bad stuff and having a strong strategy to make up for the lost links. It’s a rebuilding job I’m afraid.