Google's Webmaster Guidelines outline best practices for website owners and the use of techniques that violate our guidelines, specifically our Quality Guidelines, may cause us to take action on a site. However, not all violations of our guidelines are related to content created intentionally by a site's owner. Sometimes, spam can be generated on a good site by malicious users. This spam is usually generated on sites that allow users to create new pages or otherwise add content to the site.
If you receive a warning from Google about this type of spam, the good news is that we generally believe your site is of sufficient quality that we didn't see a need to take manual action on the whole site. However, if your site has too much user-generated spam on it, that can affect our assessment of the site, which may eventually result in us taking manual action on the whole site.
Some examples of spammy user-generated content include:
- Spammy accounts on free hosts
- Spammy posts on forum threads
- Comment spam on blogs
Since spammy user-generated content can pollute Google search results, we recommend you actively monitor and remove this type of spam from your site. Here are several tips on how to prevent abuse of your site's public areas.