Negative SEO Mitigation Tools:
The primary negative SEO mitigation method is to submit to Goole a "disavow list" of URLs and domains for Google to ignore in the following format:
http://spam.example.com/path/page-to-disavow.html domain:bad-domain.com
This action requires a "Google Webmaster Tools" (GWT) account. It is free and one can sign up on the GWT page. Sign-in and select "Create account"
Utilizing a four step process to find and mitigate Negative SEO backlinks for submition to Google:
Note that you only want to dissavow backlinks used to obfuscate your key words and confuse google as to what your website content is about. Used improperly, you will reduce your SEO if your disavow backlinks which contribute to your SEO.