Ad Stacking Fraud: A Threat to Brands and Digital Advertising

If you’ve ever clicked on an ad only to get bombarded with multiple new tabs and pop-ups, ad stacking may be the culprit. Fraudulent tactics are always evolving in the dynamic world of digital advertising to take advantage of the system.   

One such damaging tactic is ad stacking fraud, a method that silently siphons off billions of dollars while eroding the credibility and effectiveness of digital advertising.   

What is Ad Stacking?  

Ad Stacking is a type of mobile ad fraud where multiple ads are hidden beneath a primary ad displayed to users. Only the top ad is visible to the user, but a click or impression is registered for every ad in the stack without genuine viewability.   

This deceitful practice leads to wasted ad spend, distorted metrics, and eroded trust in the digital advertising ecosystem. 

How does Ad Stacking work?  

Fraudsters might use several techniques to carry out ad stacking. For instance, a fraudulent publisher script calls ads and stacks them into a single unit rather than displaying one as per ad unit. Only one ad will be visible to the user, with dozens of other ads in the placement loaded at an opacity of zero or near zero, making them invisible to the user.   

Ad stacking fraud is typically executed through the following steps  

Ad Placement: Fraudsters create a web page or mobile app and sell ad placements to advertisers.   

Stacking Ads: Instead of placing a single ad in a designated space, multiple ads are layered on top of each other.   

Impression Generation: When a user visits the page or app, only the top ad is visible, but the impressions are recorded for all stacked ads.  

Billing Advertisers: Advertisers are billed for each impression, even though most ads are never seen. 

Why is ad stacking important to understand?  

Like all forms of mobile ad fraud, ad stacking results in a wasted budget for marketers. This not only results in immediate budget losses but also distorts the data on campaign performance, potentially leading to even more significant losses.  

For instance, a marketer might think Channel A is the best for ad engagement, so they shift their budget from Channel B and C to increase the ads in Channel A. Yet, actual users are not noticing or interacting with these ads. The fake clicks and impressions deplete advertiser’s budgets for nothing in return, resulting in a poor return on ad spend (ROAS). 

Threats posed by Ad Stacking  

If you think ad fraud is a marginal problem, look at some of the higher estimates of its scale. According to recent reports, global ad fraud losses are expected to hit $84 billion by the end of 2024, with projections indicating this figure could soar to $172 billion by 2028. 

Let’s take a close look at some of the impacts ad stacking has on brands.   

Skewed campaign data, for instance, if your ad generates 15,000 + impressions but fails to generate many conversions, you'd assume that the nature of the ad was to be blamed.  

But that's not the case, what if? The ad content was excellent, and the conversion rate was quite reasonable. 

However, you might feel the need to create a new ad to replace the ineffective one due to misleading data created by ad stacking fraud.    

This prevents you from knowing anything about the effectiveness of your advertising campaigns and can have disastrous repercussions on workloads and campaign strategies because the data you are working with is fraud-driven rather than data-driven. 

Combating Ad stacking Strategies and tools  

Ensuring transparency in ad transactions and holding all stakeholders accountable can reduce the incidence of ad stacking. Frequently monitor the campaign and don’t let the ads be stacked against you, implementing an advanced ad fraud detection system such as mFilterIt Valid8, can ensure, identify ad stacking leading to fraudulent or invalid impressions through AI-ML use it distinguishes between genuine and fraudulent traffic. Relying on ad verification solutions can provide a more comprehensive defense against ad stacking. 

The path forward  

Advertisers end up paying for phantom interactions, which constitute a significant portion of their digital marketing budgets. For example, it is estimated that only 3% of digital ad spend corresponds to ads seen by humans, highlighting the extent of waste due to fraudulent activities. However, with solutions like mFilterIt brands can protect their ad spend and ensure more accurate campaign metrics.