In her latest column for ExchangeWire, Shirley Marschall pours a pumpkin spice latte (other Autumnal beverages are available) and muses what Q4 has in store for the ad tech industry.

Summer is almost over. Soon the days will get shorter, the iced lattes will give way to pumpkin spice, and wardrobes will slowly trade T-shirts for winter coats.

For most people, this is a mildly depressing thought.

For ad tech? It’s pure adrenaline.

Because Q4 is almost here! The industry’s equivalent of the Super Bowl excitement and a tax-deadline panic all rolled into one quarter. It’s advertising season! It’s when the biggest budgets hit the market, when brand managers demand flawless execution, and when every DSP, SSP, and targeting solution wants its slice of the pie. Truly the most wonderful time of the year.

If you’ve ever sat through a Q4 planning meeting, you know the drill:

• Spend the money. All of it.
• Buy the impressions. Every last one.
• Get the media plan signed off yesterday.

There’s no time for second thoughts. Q4 has always been about volume, velocity, and victory laps in January decks and not about careful optimisation.

And now, as if the seasonal chaos wasn’t enough, the AI bubble warning lights are flashing.

Yes, that B-word. Yours truly, Sam Altman himself - the man selling the AGI future - casually admitted that AI is “in a bubble.” Nvidia, Palantir, and other AI darlings saw stocks tumble after a summer of breathless hype. Analysts suddenly decided valuations might be inflated by dreams, not revenue, warning the hype could be running ahead of real-world results.

Who could have guessed?

So here we are: the industry’s most chaotic quarter colliding with tech’s most (over?)promised innovation. 

Which raises a question: when Santa Claus is coming to town, will AI take its well deserved annual leave? Will Q4 be the quarter where the 100+ AI use cases and test balloons get parked in 2026?

Q4 has never been kind to experiments

Q4 isn’t a drill, it’s the real thing. It’s money-printing season, and subtlety… doesn’t sell in Q4.

Traditionally, this quarter meant all bets off:

Brand safety guardrails loosen. 

SPO and curation projects get shoved to January. 

Incrementality testing? Please. Q4 is about reach, not restraint.

CPMs climb, and campaigns go into “more is more” mode, even if “more” doesn’t always mean “better.”

This is the time of year when even the most privacy-friendly advertisers suddenly discover the joys of mass targeting. The logic goes: “It’s the holidays, people are buying, and we need to be everywhere.”

And to be fair, sometimes this benefits quality publishers. When every impression counts, premium news sites finally get the budgets that brand safety filters kept at bay all year.

But Q4 has always been a stress test for every tool in the stack. DSP outages, misconfigured campaigns, creative QA slip-ups… if it can break, Q4 will break it. And the only thing allowed to break in Q4 is the ad budget records.

Which is why the idea of throwing unproven AI tools into this mix is… bold.

Imagine the chaos

Just imagine a digital ad blitz leading up to Black Friday where an AI creative generator is used to deliver 1:1 personalised content and it goes sideways…. 

Maybe it’s the wrong audience. Maybe the content gets weird. Maybe the content leans far left or far right for the wrong audience. Maybe it borrows tone from the wrong subreddit. Maybe it references politics. 

Or maybe an AI optimiser chases CTR so aggressively it starts buying traffic from sites you’d rather not explain to your client’s CMO. 

Outrage ensues and in Q4, there is no room for “oops.”

Which is why most marketers, when faced with shiny new tools, follow the unspoken golden rule: no tests in Q4.

Prediction season or Command+F

The good news is that Q4 is also when prediction season kicks off. 

By November, the first “Trends for 2026” decks are already circulating. (Pro tip: Command+F 2025 → replace with 2026 → done.)

So even if AI takes a backseat for holiday campaigns, the PowerPoint slides will be full of AI agent elves running the ad shop by next year.

Because nothing says “innovation” like promising it will happen after the holiday chaos is over.

So will AI sit this one out?

The real question is whether Q4 2025 will mark the moment AI in advertising grows up or gets benched until the new year. 

Will we see AI quietly powering targeting, bidding, creative, and measurement in ways no one notices? Or will advertisers decide that when real money is on the line, the machines can wait until January?

Same procedure as every year? Or will the AI elves finally earn a seat at the holiday table?

Whether AI takes over or takes the quarter off, one thing won’t change: the Q4 circus rolls on, bigger and louder than ever.

So deck the halls, spend the budgets, and may your dashboards stay green.