Ask most marketers about the state of digital advertising, and they’ll tell you it’s come a long way. From the rise of mobile to the seemingly inevitable virtual reality takeover, digital advertising is advancing. But, there’s one area where it’s still lacking: fraud detection and prevention.

Billions are lost to ad fraud annually. We’ve surveyed brand and agency professionals, and realized that as much as 37% of the respondents are unaware of how, and even if, fraudulent activity has affected their advertising efforts.

As a marketer or advertiser, the more you know about digital ad fraud detection, the better you’ll be able to prevent it. Here are the different types of ad fraud you should know about.

1. Search Ad Fraud (CPC)

Search fraud is one of the top areas where advertisers are losing the most money to ad fraud.

Search Ad Fraud

Search fraud involves putting up fake websites that target the most expensive keywords, which attracts advertisers by making their site look like a well-established and reputable publisher.

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Advertisers purchase ad space on these sites in order to advertise against the popular keywords. Then, the owner of the fake site will use bots to click on those ads, which generates a CPC revenue for them.

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2. Affiliate Ad Fraud (CPA)

Also known as "cookie stuffing," this ad fraud targets affiliates’ commissions. Brands will reward affiliates who talk about their products or services and attempt to drive people to the website to make a purchase.

Affiliate fraudsters use bots to send traffic to affiliate sites, and then employ cookies to track that traffic. If any of that traffic converts and makes a purchase, the fraudster is able to siphon away money that’s actually meant to be an affiliate’s commission.

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3. Pixel Stuffing and Ad Stacking (CPM)

Pixel stuffing and ad stacking both cause you to pay for impressions you’re not actually getting.

Ad stacking occurs when ads are literally stacked on top of each other within a web page, but only the top ad shows. However, when a user visits that page, an impression is counted for each of the ads, and all of the advertisers are charged, even though only one of the ads was seen.

Ad StackingSource: FunMobility

Similar to ad stacking is pixel stuffing, although this time, none of the ads are seen. Publishers will "stuff" ads into the pixels of the page, so they’re technically still there when a page loads, but they’re impossible to see. And even though users can’t see them, advertisers are still charged for the impression.

Video ads can also be stuffed into a pixel. Have you ever visited a web page and audio starts playing, but there’s no video to be seen anywhere? That’s probably because it’s a video stuffed into a pixel, so you can’t actually interact with it, even if you wanted to.

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4. Ad Injection (CPM)

Some of the biggest brands and sites in the world have fallen victim to ad injection at some point. Ad injection occurs when fraudsters offer consumers a seemingly innocent browser toolbar or extension to install that actually turns out to be software that injects ads onto unsuspecting sites.

When fraudsters inject ads onto a site, they never actually paid for that ad space. Most of the time, these ads are damaging to the site because it could advertise inappropriate content or show a competitor’s ad. After all, do you really think Walmart wanted to sell advertising to their competitor, Target?

Ad InjectionSource: MarketingKeys

Ad injections not only damage a site’s reputation; they can also slow it down to the point where consumers don’t want to stick around for the page to load.

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Users might see ads on a site that never wanted to display advertising, or there might be a video stuffed into a pixel that plays audio over the site’s content with no way to turn it off. It can also devalue the site as a good ad publisher because of the type of content shown in these injected ads.

5. Traffic Fraud (CPM)

Traffic fraud isn’t a result of bots finding your website; instead, this one originates with publishers. In order to increase the traffic to their site (and therefore the price they can demand for advertising space), publishers will buy traffic.

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This traffic is usually purchased from third-party sites, who generally have the highest percentage of fraudulent traffic. So, this means you could be paying the premium price for low-quality traffic that will never convert, let alone engage.

6. Domain Spoofing (CPM)

Domain spoofing can be incredibly hard to detect, which also makes it the most lucrative for fraudsters.

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It only takes a single line of code to become a victim of domain spoofing. Fraudsters can use it to change the URL of their sites to copy the URL of a more reputable site. So, you’ll be tricked into thinking that a fraudster’s site is actually the site of a very reputable publisher, like the PayPal example below. If you log in on this spoofed domain, you’re probably giving fraudsters some very sensitive financial information.

Domain SpoofingSource: Wikipedia

Fraudsters will take this "reputable" site and sell advertising on it at a discount, so it looks like you’re getting a great deal for ad space on a premium site. In reality though, you’re paying the almost-premium cost for less than quality space. Usually, your ad will end up on a site with questionable content, such as a piracy or porn site, which could ultimately damage your reputation.

Related Post: Domain Spoofing: How It Hurts Your Brand

7. Lead Fraud (CPL)

Lead fraud can come from two places: humans and bots.

Human fraudulent traffic is usually a result of publishers buying traffic for their site. A lot of "work-from-home" schemes involve hiring people to interact on the sites that buy traffic. So it looks like your ad is getting lots of clicks and those clicks are even signing up and becoming leads, but they’ll never actually convert.

A lot of the fraudulent traffic that comes from humans also affects social media advertising. Click farms have become a very lucrative business, because they’ll sell likes and shares to social media profiles in order to boost organic reach, but with many of the social media algorithms, it actually hurts those profiles more in the long run.

Fraudulent bot traffic used to be fairly easy to detect, but recently, they’ve become more advanced.

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Now, they can easily mimic human movements, generate false ad impressions, and even fill out lead forms. You’ll think you’ve gained a valuable new lead as a result of your ad campaign when in reality, you’ve just paid for yet another bot program.

Bot TrafficSource: Bloomberg

8. Retargeting Fraud (CPL)

Similar to lead fraud, where fraudsters program bots to mimic humans, a lot of times they’ll also commit retargeting fraud. These bots can be programmed very specifically to seem like the ideal consumers in order to trigger a retargeting campaign.

Then, once again, you’re spending your ad dollars targeting fake consumers, and you may even increase your advertising budget to try to ensure you keep these leads.

What You Can Do

Some types of ad fraud can be hard to catch, let alone monitor, but you can take a few preventative measures:

  • Request Transparency. Ask your publishers exactly where their traffic is coming from. If they can’t (or won’t) tell you, avoid them.
  • Third-Party Monitoring. Real-time monitoring from a third-party source can help you stop the fraudsters before they cost you money.
  • Search Incognito. Search for your site with your browser in incognito mode. This way, you’ll be able to see exactly how your site looks and functions for other users.

Too much time and money is being lost to ad fraud. The more you know about ad fraud and the different ways it can hurt you, the better prepared you can be. Make sure you know what you can do to stop it.

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