Negative SEO has exists for long time and there are ways how to does it. The basic explanation of this method is the SEO practice using black hat techniques on another site. For the most part, a negative SEO attack is being done by a competitor using malicious manner to lower other website's ranking in search result. Kristi Hines from Search Engine Watch gives her thought on negative SEO,
"I consider negative SEO anything that could harm your reputation, visibility, or traffic in search."
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