What is Google Algorithm Filter? – Definition
An algorithm filter is a Google penalty, which is automatically imposed on the site. It is very difficult to identify and solve. It can be noticed by a sudden drop in the search results on specific keywords (especially on the ones in TOP 10) and lower web traffic.
Information about imposing this filter from Google doesn’t appear in Google Webmaster Tools.
How to Check If a Google Algorithm Filter Was Imposed on Your Website?
In order to check if your website has a Google algorithmic filter, you need to analyze keyword ranking in Google. If they have recently reached high positions and now they are in distant places or removed from the search results, and suddenly the website loses traffic, this indicates that most probably Google imposed algorithm filter. There is no clear reason for applying this type of filter.