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Anatomy of Mobile Ad Fraud: Ad Stacking

Updated: Jun 20, 2022

To put it simply, Ad Stacking means stacking up adverts on top of each other. Ad Stacking is a very common mobile ad fraud practice wherein, multiple ads are stacked beneath one another in a single ad placement on mobile apps or websites for generating fake impressions. Only the top ad is displayed to the user/visitor. However, every ad in the stack receives a click or impression, because of its placement. As a result, advertisers are forced to pay for fraudulent impressions or clicks which are not intently clicked by the visitor.

Ad stacking is among the most widespread types of ad fraud. Moreover, Ad stacking is most commonly associated with mobile ads. It accounts for 20% of global ad spending, stealing hard earned money of marketers and businesses of all kinds. That is because it is more prevalent in click-based campaigns and businesses spend a huge section of their budgets on Cost per Click (CPC) or Cost per Thousand (CPM) campaigns.

But how does this work exactly? How can fraudsters defraud big corporations or fool regular internet users? Let's find out

How Does Ad Stacking Work?

Ad stacking is just what it sounds like, stacking ads on top of each other. On a normal course of action, it would look like a pile of sheets. However, digital marketing and the internet work differently. Herein, by stacking, fraudsters actually hide several ads beneath the main ad, and the users can only see the advert at the top. When a user clicks or watches the top ad, the other stacked ads also get clicks or impressions and are thus recorded for the same.

Ultimately, advertisers are paying for clicks and impressions which was not intended by the user, but somehow have a record of click or impression. This way fraudsters steal ad budgets from advertisers and marketers and increase ad revenue for publishers who are also engaged in the scheme by stacking advertising.

On a website or any fraudulent platform, the publisher will summons ads and stacks them into a single ad space instead of displaying one ad per ad unit. Only one ad will be shown to the user, with the remaining ads loaded at zero or near-zero opacity, leaving them invisible to the user. A click on one ad unit resulted in a click on all of them. These adverts are never seen by the user, yet advertisers pay for these fake impressions or clicks since they trigger an ad impression.

This way, fraudsters make money from multiple channels by generating just one click. With additional ad stacks, clicks, and impressions, the threat escalates tenfold.

Ad Stacking | Com Olho

The impact of Ad Stacking

As previously stated, Ad Stacking is a cause of great concern for marketers. Moreover, according to research from 2018, Ad Stacking, together with Click Spam, amounts to 27% of total ad fraud, trailing only App Install Farms (42%) and Click Injection (30%). And just like other forms of mobile ad fraud, Ad stacking also lead to wasted ad spending and biased campaign statistics for marketers.

Advertisers and Marketers might get the desired traffic and impression from their ad campaigns. But in reality, most of those data would be untrustworthy and the amount spent on such would be a waste.

Ad stacking is mostly used when advertising is paid on an impression-based or click-based model. Brands often pay ad networks on a cost-per-thousand (CPM) or cost-per-click (CPC) basis, but their budgets are depleted because of fake clicks and impressions. By layering ads on top of each other, advertisers waste money, resulting in a low return on ad spend (ROAS).

In addition, this will also have adverse effects on a company's marketing strategies. Any marketer who isn't aware of such malicious practices will believe in the misleading reports and poor performance results. Ultimately, this will push firms to increase their advertising spending, resulting in more money for scammers and fraudsters.

Not only marketers, but publishers can also fall victim to Ad stacking. It can potentially harm the reputation and credibility of publishers who are unaware of the false ads they are displaying. Finally, the user or the visitor might not suffer any monetary losses, but they are nevertheless flooded with multiple ads on their browser.

How to prevent Ad Stacking?

Every day, fraudsters are billing multiple advertisers for single clicks and are simply draining large amounts of advertisers' money. But this functionality can also aid in the detection of fraudulent activities. Publishers can detect numerous impressions or clicks from a single user at the same timestamp, indicating that many ads were piled on top of each other. It is the publisher’s obligation to report these malicious practices on their platform

From an advertiser’s perspective, brands must regularly check their campaign performance and identify if the same user or device is clicking on several adverts with the same timestamp. Monitoring the conversion rates of campaigns on a regular basis will help detect anomalies. A high number of impressions combined with a low conversion rate is usually a sign of ad stacking.

Further, there are also cybersecurity software and tools that employs advanced algorithms to detect and prevent fraudulent behaviour.

These were a few techniques to figure out if you are targeted by ad stacking. When Ad stacking occurs, these can help identify it.

In Conclusion

The digital ad space has become a playground for cybercriminals. Even capable mobile gadgets are also subjected to cyberattacks. Fraudsters are defrauding marketers, networks, and even users, all at once. They constantly find a way to steal money when marketers increase their investments in digital advertising. Thus it is the responsibility of brands to take proactive and preventative measures to ensure that mobile ad fraud does not impact their operations.

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