Negative SEO refers to the use of black hat SEO strategies in order to ruin another websites ranking. These strategies are employed by competitors looking to sabotage your business. It can be hard to defend yourself if you dont know what you should be looking for. Find a comprehensive content optimization ebook that teaches you more about SEO and how to improve your own site’s security (On-Site and Off-Site) Find backlinks that look spammy and look for plagiarized, republished content on other websites.”]
Source: https://gbhackers.com/how-to-protect-your-site-from-negative-seo/