Avoid Negative SEO
At long last, site owners now have the option to remove any illegitimate or dishonest links that creates a negative SEO on their websites. The much awaited Google Disavow Link Tool is now available through Google Webmaster Tools service.
A Page Rank can be valued through the number and quality of links pointing to your site. Low-quality spam links can get your de-indexed by Google or at the very least significantly lower your page rank.
If you have been spamming around creating a link juice by submitting to low quality directories or bookmarking sites, selling, buying or exchanging links, you are then held liable for violating the Google’s quality guidelines. In some instances, it is also possible for a third-party website to create a back link to your page without your knowledge. Though you may not have any control over it still, you are accountable for losing your page rank.
But with the new Disavow Link tool option, webmasters can now direct Google to ignore any link backs to their website from select pages or the entire domain. This can easily be done by going to the new Disavow Links page under Google’s Webmaster Tools and identify the pages or domain in the specified format.
There is nothing to lose if you start using the Disavow Link Tool if only for the reason that it exist to avoid negative SEO.
If you want to read more about the Google guide on Disavow Links, you may visit http://googlewebmastercentral.blogspot.com/2012/10/a-new-tool-to-disavow-links.html.