WPP and Dentsu have left much of the adtech world in a conundrum after the two holding companies pulled back from The Trade Desk’s (TTD) direct-to-publisher OpenPath initiative.
ADWEEK reported that the agency groups’ exit from the scheme was due to growing friction with demand-side player TTD over what it said were “hidden fees” and a lack of transparency around ad placement.
OpenPath, which launched as TTD’s attempt to give ad buyers direct access to publisher inventory without routing through sell-side platform intermediaries, was positioned by CEO Jeff Green as entering a “steep acceleration phase” in 2025, and if successful, the initiative could offer a viable alternative to Google’s hegemony.
ADWEEK reported that it had seen text messages from a source at Dentsu confirming it had disabled OpenPath. It cited an anonymous executive at WPP familiar with the matter who said it had moved away from OpenPath soon after it launched.
Replying to a LinkedIn post from ADWEEK, Ian Colley, TTD’s chief marketing officer and EVP said the article “fundamentally misunderstands” how the tool works, he added that ADWEEK declined to include its full reply.
Ori Gold, CEO and co-founder at Bench, a digital media agency, doesn’t see WPP and Dentsu’s retreat from OpenPath as evidence of systemic failure—but rather a breakdown in negotiations.
“OpenPath is only one way that you can buy through TTD, and not necessarily the entire ecosystem. We see TTD as a market leading technology for programmatic and RTB lines.”
Gold argued that OpenPath should be viewed in the context of TTD’s broader positioning as an independent technology layer—distinct from closed ecosystems that control inventory, tech and reporting.
“I think that what they’re actually doing is breaking down the powers that were there before by creating a quicker path to the inventory or quicker path to buy from advertisers.”
However, that “quicker path” might be the cause of the friction with holding companies.
“I believe some of the larger networks and larger entities don’t necessarily like it, because they might see less accounting transparency on their side, which means they have less control of some of the ways that we can buy the inventory,” Gold said.
As an independent agency, he said Bench is “less concerned with legacy buying structures” and is focused on advertiser outcomes instead.
“For us as an independent we do not really care from whom we buy, we do not really affiliate with anyone else, so OpenPath actually seemed like the right decision to reduce fees.”
“When we look at transparency we are looking at outcomes and what the value is to the advertiser on the other side.”
So far, he said, OpenPath is delivering.
“For us at the moment, OpenPath seems to be doing more for the advertiser rather than less.”
‘Sitting on the fence’
Claims of “hidden fees” failed to convince Gold that OpenPath represents a new transparency crisis, and instead places the dispute within a wider shift across adtech, as DSPs, SSPs and publishers increasingly move into each other’s territory.
“We see SSPs starting to sell directly, and we see the DSPS, including TTD, starting to give backwards and dealing directly with the suppliers. So I think the whole ecosystem is changing.”
While Gold acknowledged that TTD’s deeper move into supply represents a positioning shift, he stops short of calling it a trust breach. For now, Bench remains cautious but engaged.
“For us, we are sitting on the fence, testing it, understanding what the outcomes are”.
The coordinated pullback by two global holding groups is significant, he concedes—but not conclusive.
“I think it’s big, but let’s see that what’s happening with the other groups. That will be more of an alarm, rather than a concentrated shift of power where two big entities trying to arm wrestle.”
If more networks or major advertisers follow, that could signal deeper issues.
“I think if we see more networks and agency than larger advertising is flocking away. Maybe there’s some more truth in it, rather than a political arm wrestle,” said Gold.
‘Struggling to deliver’
Yango’s media director Luke Creeley believes WPP and Dentsu’s decision to walk away “suggests OpenPath is struggling to deliver”.
He said as an independent agency they aim to work “as transparently as possible”.
“We aim to secure the best outcomes for our clients, so any lack of transparency and potential hidden fees can certainly compromise this,” Creeley said.
“For years, TTD has championed the ‘open internet,’ but if OpenPath is masking fees or operating as a black box, it compromises this overall approach.”
Creeley said although Yango sees TTD as one of the partners it uses in its agnostic approach, “a lack of transparency makes it harder to consider going down this route over other alternatives that can provide us more control as well as transparency.”
“We’ve been assessing our supply paths closely and encourage everyone to do the same.”
According to The Media Store’s performance director, Annie Marendaz, OpenPath is “a great step, in theory, to simplify the supply chain” but “without full transparency of where ads are served, it defeats the purpose.”
She believes the exit from OpenPath is “more about the loss of control over supply and SSP partners” rather than the buying model itself.
“TTD positioned OpenPath as the industry’s white knight against Google’s walled garden, but Dentsu and WPP’s exit proves you can’t fight a black box by building another one,” said James Taylor, founder and CEO of retail media player Particular Audience.
“When a platform is taking up to a 20 per cent effective cut while obfuscating exactly where the ads are running, it ceases to be an alternative to the ‘ad-tech tax’—it just becomes the new tax collector.”
Taylor emphasised that his company prioritises “glass box transparency” and “advertiser precision” in its targeting technology.
“At a 20 per cent take rate you’d sure as hell need to offer the same if countering the walled gardens.”
However, Colley, described OpenPath as “just one example” of their supply chain initiatives.
“TTD doesn’t ‘push’ spend to OpenPath. It’s not a marketplace or curated inventory. OpenPath is simply a supply path option to ad impressions an advertiser would already be targeting. OpenPath is offered at cost to the ecosystem. We’ve been clear about that. There are no hidden fees beyond that. If OpenPath is selected by an advertiser, it’s simply because it’s the cleanest, most cost-efficient path,” Colley wrote.
“Adweek also declined to include our full comment on this. But I’ll include it here: OpenPath is just one example of our supply chain initiatives — all developed in collaboration with brands and agencies — to drive transparency, value and choice. OpenPath is just one option that buyers have en route to any given impression, and spend flowing through OpenPath has been growing steadily over the last year or so. The primary reason that OpenPath has been so successful is that it is the clearest, most cost-efficient path with the highest signal. For many buyers, this has become a key focus area of our supply chain collaboration, and OpenPath has become a critical beacon of value.”
B&T contacted Dentsu and WPP on Monday, who both declined comment.
However, B&T understands WPP doesn’t use OpenPath in Australia at all.
