When used effectively SEO is a powerful tool to attract high-quality traffic and conversions to your website.

But SEO also has a dark side. While most people use SEO to enhance their own website, some people use it to impair or attack the websites of others.

The set of tactics that are used in this way are commonly referred to as “negative SEO.”

Some of these tactics may provide a short-term benefit for the instigator when used very carefully, however, all negative SEO tactics are very high risk (and sometimes even illegal) and will invariably result in some kind of penalty.

It’s difficult to say how common the use of negative SEO tactics is, but it does happen. If your website is central to your business, it is helpful to be vigilant and educate yourself about the different types of negative SEO strategies that are out there.

Here is a rundown of the most common techniques, and what you can do to guard yourself against them.

Negative SEO Defined

SEO practitioners work with a number of different tools in order to gain traffic and rankings, while also minimizing risky behavior in order to avoid search engine penalties. In negative SEO, the opposite is true. Common SEO tactics are turned on their heads, and used in ways that might destroy a competitor site’s credibility and rankings.

Some of the most common negative SEO tactics include:

Spammy Backlinks

Backlinks are the cornerstone of any good SEO strategy, and normally, receiving links from other sites is a good thing. However, if someone suddenly points thousands (or hundreds of thousands) of poor quality links to your site, it will look to Google as if you are artificially inflating your link profile, and you’ll most likely get slapped with a penalty.

Duped Content

Duplicate content, or the same content appearing on more than one URL, is something that you most website owners try to avoid at all costs. By copying and pasting your content onto another domain, someone practicing negative SEO could get you in trouble with Google, and again, hit with a nasty penalty.

Spammy Anchor Text

If you use email, then you’ll know that certain words like “Viagra” or “Cialis” will trigger your spam filter. Similarly, if someone uses these terms in anchor text links to your site, then it can be a red flag for Google. If you get enough of these spammy anchor text links, then it could affect Google’s quality rating of your site, and result in a loss of traffic and rankings.

Fake Reviews

Fake reviews on sites like Yelp or Facebook not only affect your brand’s reputation; they can have an impact on your local SEO too. Search engines use review data to help determine rankings, so a large number of negative reviews can impact your traffic and conversions.

Removing Backlinks

Sending low-quality backlinks to your site is one way to impact your standing in Google. Another, trickier way is to remove your best backlinks. Often, Google will interpret this as a sign that your site has dropped in quality. While this tactic is a little more complicated, it can be done. Never assume that your backlinks will last forever.

Hacking

Finally, an extreme (and illegal) form of negative SEO is hacking a website for nefarious purposes, such as installing malware or adding low-quality content to its pages. If Google notices that your site has been hacked, it will immediately move to warn users and possibly even remove it from search listings entirely.

How to Protect Yourself

The best way to protect yourself from negative SEO is to run regular audits and maintenance of your site, including analytics reports. You should be doing this as part of your SEO and security regimen anyway, but here are some more specific tips to help protect your site against negative SEO:

Link Monitoring

As part of your overall SEO maintenance, you should be regularly monitoring your backlink profile. As well as looking for high-quality links you’ve won, you should also be checking for unusual activity, like sudden spikes in links, or links from unusual or suspicious-looking sites. Unusual traffic activity, like sharp increases or dips, can also be indicators of link-related negative SEO.

Duplicate Content Monitoring

You can easily check for duplicate content or plagiarism using tools like Copyscape. If you discover that someone has plagiarized your content, you should reach out to the site’s editor first. Sometimes duplicate content is published by mistake. If you believe that your content was stolen or published with malicious intent, you can report it to Google using their Online Copyright Infringement form.

Monitor Brand Mentions

Most businesses monitor online sentiment and reviews, and most tools used for brand monitoring will obviously show up negative reviews. If you receive reviews that look fake, sites like Yelp usually have a reporting process that you can use to alert them to suspicious content. If fake reviews are a pervasive problem across multiple sites, then you may want to consider hiring a reputation management specialist.

Regular Site Audits

Whether you think your site is at risk of being compromised or not, conducting regular site audits is essential. Site security is obviously paramount. If you’ve been hacked, you’re going to want to know as soon as possible so you can minimize the damage. Beyond that, you should be constantly looking for unusual activity in your analytics, for example unusual bot activity, URLs you don’t remember creating, and unusual spikes or dips in traffic.

While Google is constantly improving and cracking down on negative SEO tactics, the responsibility is really on you to monitor your site and audit it regularly to ensure everything is in working order.

For more great content on black hat and grey hat SEO techniques, check out my interview with Matt Diggity on the Marketing Speak podcast.