In 2015, Google saw an 180% increase in hacked websites in comparison to 2014. The number of sites with thin, low-quality content also rose over the year. On 2 May 2016, Google announced that it has been combating sites that have been hacked, as well as low-quality sites. Sites that use content scraped from other sites are considered to be low quality or of little value to users, as they are employing webspam techniques that go against Google’s guidelines for webmasters.
In an effort to clean up SERPs, Google called on its hacked spam algorithm. The hacked spam algorithm was released in October 2015 and resulted in the removal of the majority of hacked and low-quality sites. As well as using the hacked spam algorithm to remove hackers and sites with bad content, Google sent out more than 4.3 million messages to notify webmasters of manual actions on their sites. As a result of this, Google saw a 33% increase in the number of sites cleaning up spam in order to go through the reconsideration process.
During this time, Google received more than 400,000 spam reports. Additionally, 65% of the spam reports were acted on by Google, and up to 80% of those acted on were considered as spam. More than 200 Google Hangouts took place in order to answer tens of thousands of webmaster queries, including more than 35,000 by users considered to be webmaster top contributors. The Hangouts were hosted in 17 languages. Google also increased its participation in the Google webmaster forums, in another effort to answer Webmasters questions.