Negative SEO is a branch of SEO that largely came into existence with Google’s Penguin Update. For the first time in SEO a search engine was prepared to lower your ranking based on what it perceived to be a site gaming the system. Not only did site’s change the way they promoted themselves but this created a very real opportunity to harm competitor’s sites.
All you have to do to is mimic spammy promotion of a site to draw Google into penalizing that site. This can include:
- Building too many unnatural backlinks from low quality sites too quickly to have been organic
- Using anchor text with adult themes or words associated with low brow tactics.
- Associate the competitor or target site with link building schemes, such as a PBN.
- Duplicate content thereby watering down the value of their original content.