It is quite obvious in the webmaster world that spammy links or too many backlinks from a site can badly affect the rankings of a website, and can bring down the site's rankings to a very low level. In a competitive world like today, people take every possible step to be ahead of all in their respective fields, either by becoming better through enhancement or by letting the competitors down in every possible way.
Even in Search engine optimization industry, tough level competition exists. Every site owner wants their site rankings to be higher than the competitor's site, and they can go up to any extent to attain such targets. This is where manipulation enters the industry. A competitor could hurt a sites ranking by adding a lot of backlinks to a site, which gets the respective site's ranking to drop; as search engines consider it to be aggressive link buying. There are many other ways of link attack adopted by spammers in order to hurt the rankings of their competitor's sites. They post junk comments and links in the blog posts, or do a spam link attack on the site, Link injection spam etc. The innocent site owner may not even be aware of such a link attack on his website. So it is mandatory for every site to get reviewed by Google webmaster guidelines and keeps monitoring the site for any link attack.
Competitor's link attack on a website can also be referred to as Negative SEO attack where a website owner buys links and points them at a competitor's site with an intension to damage their rankings. Due to all this Google gives the site owners to "Disallow" the links that the site owner doesn't want to reflect in their sites. Disallowing links from a site should be done very carefully as once the links are disallowed they will not be reflected in the site again. A site owner might want to disallow links from his site that are completely irrelevant and seems to be appearing from an unknown source. This might help the site owner to protect his site from link attacks.
I as a Seo company owner have tried to add few backlinks in a site in order to see the impact on the rankings of the site. I noticed that the site was ranking high for a particular keyword, but drastically dropped in rankings after the backlinks attack. It is understood that Google takes action against spammy sites.It's extremely important to monitor SEO factors that can easily be manipulated by competitors such as backlinks and reviews.
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Working example of Negative SEO attack by a competitor
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