The 6 biggest ad tech stories of the year — and what they mean for 2026
The 2025 advertising ecosystem was defined by sweeping changes: high-profile mergers, regulatory battles, the supposed rise of agentic AI, TV measurement feuds and more.
In a word, it was defined by transformation.
That means 2026 could look very different, and media buyers, brands, publishers and everyone in between will need to adapt to the new ecosystem.
With that in mind, we looked back at the year’s six biggest stories in ad tech — not “6,7,” just six — and what they may mean for the year ahead.
Google was ruled an ad tech monopolist
A federal judge ruled that Google maintained an illegal monopoly in two ad tech product markets.
We’re still awaiting Judge Leonie Brinkema’s decision on remedies. The U.S. Department of Justice is pushing for structural changes, including the forced sale of Google’s ad exchange, AdX.
During closing arguments last month, Brinkema appeared skeptical of structural remedies.
But at any rate, Google has faced immense regulatory pressure this year, both in the U.S. and elsewhere, which could reshape the global advertising power dynamic.
The company even recently said it would change its ad tech products in Europe to avoid an EU-mandated divestiture.
Agentic advertising made waves. Is it more than just hype?
Advertising is an industry of endless standards and frameworks, and that’s no different for agentic advertising.
A group of companies have launched Ad Context Protocol (AdCP), a technical standard designed to enable agentic AI in the advertising workflow.
Anthony Katsur, CEO of IAB Tech Lab, told The Current that the industry doesn’t need “another trade group,” and that the Tech Lab already does many of the things AdCP claims to do.
Soon after, Tech Lab announced Agentic RTB Framework (ARTF), to standardize agentic across programmatic, building on existing Tech Lab standards.
“Although AI solutions will increasingly take shape, the industry should expect several false starts in deploying agentic solutions,” Katsur predicted for the year ahead.
“The promise of agentic AI is real and meaningful, yet its practical application will require years of market experimentation, standardization and alignment across platforms, agencies and publishers.”
The Omnicom-IPG merger hinted at AI stress
The Omnicom-IPG merger recently closed, forming the ad industry’s largest holding company. But it also beefed up the combined entity’s AI potential.
“At the heart of the acquisition is some of the technological change that the power of the two holding companies are bringing together,” Stacy DeRiso, global brand president of Initiative, told The Current ahead of the merger.
The merger comes amid growing AI tension at agencies — something that will undoubtedly carry over into 2026.
“We’re feeling the pressure [from clients] that we must be doing something with AI while also being under a level of scrutiny that we’ve never seen before,” Jennifer Laing, senior vice president of operations at Causal, said during a panel at Advertising Week New York.
TV measurement was put under the magnifying glass
The Current reported on findings from the Video Advertising Bureau (VAB) showing that ratings across 158 TV networks fell by historic levels under Nielsen’s new Big Data + Panel measurement.
The report followed mounting pressure on Nielsen as rivals look to eat into the company’s hold on TV measurement.
Ahead of the NFL season, the league criticized Nielsen, saying it undercounts millions of viewers. Every major U.S. sports league is now eyeing new measurement partners.
VAB President Sean Cunningham believes this all could impact next year’s upfronts.
“You’ll see more change in place for the [2026] upfronts than came in the two or three decades before,” Cunningham told The Current. “It’s coming fast.”
Transaction ID changes sparked debate
In August, Prebid rendered its transaction ID (TID) unworkable across exchanges, sparking fierce response across the ad industry.
The organization eventually “clarified” the decision — another way of saying it walked the change back.
But before that, The Trade Desk CEO Jeff Green announced in an op-ed OpenAds, a new product built on the foundation of Prebid.
Some in the ad tech industry interpreted the op-ed as pitting the buy side against the sell side. But Green insisted at the Prebid Summit in October that it was about “quality publishers who are taking home less than they should be, and publishers that are taking home more than they should be.”
PubMatic Chief Revenue Officer Kyle Dozeman recently concurred that the buy-versus-sell side narrative is a “distraction.”
“Publishers need revenue predictability. Buyers need operational efficiency and inventory confidence,” he told The Current. “The question isn’t which side of the transaction you’re on, but what value are you really bringing? What innovation makes you indispensable to the success of the digital advertising industry?”
Hopefully the industry keeps that in mind for 2026.
Google pulled back on Privacy Sandbox
Maybe this one isn’t such a shock.
In October, Google announced that it was retiring many of its Privacy Sandbox technologies, due to “ecosystem feedback” and “low levels of adoption.”
The ecosystem had already largely moved on, with a focus on first-party IDs and other cookie alternatives.
But Google will continue to support some functions of Privacy Sandbox, meaning it may not be completely irrelevant in the New Year.
“Zombie like, some of its remains survive to present an ongoing threat to open web publishers,” said James Rosewell, co-founder of Movement for an Open Web.