Here, Dan Johns, partner at Tumbleturn Marketing Advisory advises on why there’s more to the Publicis, WPP and dentsu disputes than meets the eye.
Something significant happened in global adtech over the last few weeks and we haven’t seen much local commentary on it yet, especially on why advertisers should be worried and what they can do about it.
Three of the world’s five biggest holding companies have publicly distanced themselves from The Trade Desk. Dentsu, WPP and now Publicis. The stated reasons are fees and transparency, but our read is that it’s bigger than that.
What actually happened?
Let’s start with OpenPath, which was The Trade Desk’s initiative to let advertisers buy publisher inventory more directly, cutting out the middlemen that bloat the programmatic supply chain. CEO Jeff Green called it the transparent alternative to Google and predicted 2025 would be its breakout year.
Then Dentsu quietly disabled it, and WPP, it turns out, never really used it in Australia at all. Both cited concerns about where ads were actually running and fees they hadn’t agreed to.
Then came the Publicis situation last week. They commissioned an independent audit through FirmDecisions, and the findings were pointed. The Trade Desk allegedly applied its DSP fee to other charges, enrolled clients in tools without evidence that those clients had authorised it and didn’t give the auditor what was needed to verify that media and data costs were being passed through at cost.
Publicis told clients to stop using it. The Trade Desk’s stock has dropped over 80% from its December 2024 peak, and three brokers downgraded it in a week.
Understandably, the Trade Desk disputes everything. They say they never failed an audit, that the auditor requested data that would have breached other clients’ confidentiality, and that Publicis runs its own opaque practices while pointing fingers. Jeff Green posted a pointed LinkedIn response calling out agencies that wave the flag of transparency while arbitrage-ing the inefficiencies of programmatic for their own profit.
He’s not wrong about that, but it doesn’t mean the audit findings are wrong either. Both things can be true at the same time, and that’s kind of the whole problem.
The layer nobody talks about
Under all of this sits something Australian CMOs should understand. Principal Media.
This is where an agency buys inventory wholesale as a principal and resells it to you at a markup you don’t see. It’s not illegal, it’s not even unusual, but it means the agency is not acting purely in your interest on those buys.
A former WPP executive filed a wrongful termination lawsuit last year, alleging he was let go for raising objections to the holdco’s rebate practices. WPP’s counter-filing was accidentally made public in 2024, an internal memo revealing that GroupM’s principal media revenue exceeded one billion dollars globally.
When Omnicom’s CEO was asked about principal media on an earnings call, he said: everybody else you speak to in the industry doesn’t tell you the truth. It is what it is. It is a product.
Studies from the ANA suggest that globally, around half to 60% of programmatic budgets never reach consumers as quality impressions. There’s an estimated $26.8 billion optimisation gap in 2025 alone.
This is the backdrop against which the Trade Desk story should be read.
What it means in Australia
This isn’t just offshore drama either; clients of Publicis agencies in Australia, Starcom, Zenith, Spark Foundry, Digitas, are directly affected by the ‘no longer recommend’ stance on The Trade Desk. If your media is bought through any of those agencies, you should be asking questions right now.
Independent ad fraud researcher Dr Augustine Fou has been making this argument for years. Ad fraud and fee opacity aren’t technology problems; they’re incentive problems. Everyone in the chain profits from volume and complexity, and the advertiser is the only party whose interests are served by simplicity and transparency. Unsurprisingly but unfortunately, the advertiser is usually the last one to find out.
The thing Jeff Green got right
In his LinkedIn response, Green wrote that some players wave the flag of transparency publicly but run from it in practice as they arbitrage the inefficiencies of programmatic.
Principal media is exactly that. Agencies are making money from the opacity of a system they’re supposed to be navigating on your behalf.
But here’s the thing, Green’s criticism applies to a system that The Trade Desk is also part of. The question isn’t who the good guy is in this fight. The question is whether you, as the advertiser, have enough visibility into your own spend to know how much of it is working.
If the answer is no, that’s not an accident.
This opinion piece was first published on LinkedIn.
