For years, Google hasn’t just participated in the digital advertising marketplace – it has effectively run it.

Now, that dominance is at the center of one of the largest antitrust cases ever brought against a technology company.

The consolidated federal antitrust case (In Re: Google Digital Advertising Antitrust Litigation, 1:21md3010) alleges Google violated the Sherman Act by unlawfully monopolizing the digital advertising technology stack (“ad tech”) stack, the complex infrastructure that powers how online ads are bought and sold.

The impact? Billions of dollars, spanning product markets and thousands of advertisers and publishers.

What Is This Case About?

At a high level, plaintiffs allege as early as 2008, Google used exclusionary tactics and self-preferencing strategies to entrench its control over digital advertising markets. 

According to the complaint, Google’s conduct allowed it to:

• Inflate advertising prices
• Suppress publisher revenue
• Block or disadvantage competitors
• Increase exchange “take rates”, ultimately driving higher costs passed down to consumers

In other words, the allegations aren’t just about competition theory. They’re about whether one company controlled both sides of the market – and set the rules in between.

While the court denied certification of the advertiser class, the publisher claims are continuing to move forward in the U.S. District Court for the Southern District of New York.

Why the Digital Ad Market is So Complicated

To understand the scope of the case, it helps to understand how digital display advertising works.

The display ad market resembles a high-speed financial trading exchange. Publishers (website owners, app developers, podcast platforms, content creators) sell ad inventory. Advertisers bid to place ads. Brokers and exchanges facilitate the transaction.

Now here’s where it gets interesting.

Google doesn’t just participate in this system. They basically operate it:

• Google represents buyers
• Google represents sellers
• Google operates the largest exchange (AdX)

In the electronically traded world of display ads, Google has been described as the pitcher, the batter, and the umpire – all at once.

Nearly all online publishers – large and small – rely on Google’s tools to sell ad space through centralized electronic trading venues known as ad exchanges. Plaintiffs argue that this structure created an anticompetitive chokehold over the digital advertising stack.

The Scale of What’s at Issue

This case spans multiple product markets and thousands of publishers and advertisers. The alleged damages are substantial.

For context, Google’s advertising revenue has grown dramatically in recent years – from roughly $123 billion in 2020 to well over $250 billion by 2025.

That growth, in and of itself, isn’t unlawful. But plaintiffs argue that part of that dominance was achieved and maintained through conduct that distorted competition.

If proven, the implications for the digital advertising industry could be transformative. 

Why Publishers Should Care

If you are a publisher running display advertising through Google or AdX, this case directly touches the infrastructure that drives your ad revenue. 

The questions are the heart of the litigation include:

• Were exchange fees artificially inflated?
• Were publisher revenues suppressed?
• Were competitors unfairly excluded from the market?
• Did Google’s control over multiple layers of the ad tech stack distort pricing?

The outcome could impact potential recovery opportunities and future market structure.

What Comes Next

The publisher claims are continuing to progress, and this litigation remains one of the most closely watched antitrust matters in the technology sector.

Given the complexity of the digital advertising ecosystem – and scale of potential damages – publishers should not assume this is “just another tech lawsuit”. It could reshape how digital advertising markets operate.

If you are a publisher that monetizes through Google’s ad technology stack or AdX, now is the time to stay informed and evaluate your options.

CCC is monitoring this case closely and can help assess eligibility, track developments, and support publishers every step of the way.