On Oct. 17, Google started the rollout of its newest Penguin algorithm, which has been dubbed Penguin 3.0. It has been over a year since the last major update of Penguin, which happened on Oct. 4, 2013.
The Penguin update was created to find sites that are spammy and do not comply with the Google guidelines, especially when it comes to linking. Sites that fall under the category above receive a manual action penalty in which Google tells you that you are being penalized, or an algorithmic penalty, which is not as significant but does affect search visibility and rankings.
After the last update, Google released the disavow tool, which allowed webmasters to submit links and domains of sites they no longer want associated with their own site, asking that link be removed. Many webmasters and individuals in the SEO industry have been waiting for what seems like an eternity for this update.
It is important to carefully monitor your web presence to look for changes in impressions, as that will be your biggest indicator on the impact of Penguin for your site. Full rollouts of major updates usually take a week or so to successfully reach across the web, so make sure you are constantly checking for changes in impressions and rankings.
If you have submitted a disavow before September, you should see a change in your web presence throughout the week. Also, if you have a bad backlink profile, you could potentially get penalized. It is important to keep a clean, natural backlink profile, as this will pass the filters of Penguin.
Remember that not all sites will see changes. Google has said that it has a new system in place that will allow for more frequent refreshes.