Omnicom has commissioned a third-party audit of The Trade Desk, telling clients it wants to review the platform’s billing practices after rival holdco Publicis raised concerns about hidden fees.
According to an Ad Age report, the move follows Publicis’ recent audit of the demand-side platform, which the French holding company said uncovered charges tied to features and services it had not approved.
Omnicom says initial review found no client impact
In a memo to clients, Omnicom said the audit formed part of an added diligence process in light of Publicis’ findings. The company also said it had already completed an initial contractual review that did not identify any negative impact on clients from its dealings with The Trade Desk.
Omnicom declined to comment publicly, according to the report.
The Trade Desk confirmed that Omnicom was reviewing its contracts and described the process as part of routine oversight.
“The Trade Desk has a successful and long-standing relationship with Omnicom, that continues to go from strength to strength based on mutual goals of transparency, innovation and performance,” a representative for The Trade Desk said in a statement to Ad Age.
“Omnicom has a rigorous and detailed approach to managing their contracts, governing campaigns and evaluating performance. They routinely monitor all campaign activity on TTD. As outlined in Omnicom’s email to clients, Omnicom Media’s analysis and reviews have not uncovered any issues whatsoever.”
Big Four firm to lead review
Omnicom told clients that the auditor would be one of the Big Four accounting firms, although the firm’s identity was not disclosed publicly, according to Ad Age.
That detail is notable because Publicis used FirmDecisions for its audit. The Trade Desk later criticised that appointment, arguing the consultancy was not among the most widely recognised audit firms.
Why it matters for ad tech transparency
The dispute has intensified debate around transparency in programmatic advertising, particularly how agencies and clients are charged for ad tech services.
Publicis advised clients last week to refrain from using The Trade Desk’s ad tech, saying its audit found hidden fees linked to services the holdco had not sanctioned.
The Trade Desk rejected those findings and said some of the information Publicis wanted could not be shared because it involved confidential agreements with other holding companies and third parties.
Broader pressure on The Trade Desk
The disagreement comes as The Trade Desk faces growing pressure from multiple sides of the market. Agencies are increasingly seeking lower-cost programmatic buying options, while larger platforms such as Amazon and Google can reduce fees in ways that independent ad tech businesses cannot easily match.
The Trade Desk has argued that its value lies in operating as a neutral demand-side platform, unlike Amazon and Google, which also own media inventory and compete for advertiser spend.
At the same time, agencies are placing greater focus on the supply side of the market, including direct relationships with supply-side platforms, publishers, and connected TV providers.
Tensions with agencies have been building
Tensions between The Trade Desk and major agencies have been rising for more than a year. That friction escalated after the company said it would increasingly pitch directly to brands for advertising budgets.
Jeff Green, chief executive of The Trade Desk, has also publicly criticised agency practices such as principal media buying, where inventory is resold at a markup.
Defending the company last week, Green wrote on LinkedIn that some industry players “want to wave the flag of transparency publicly, but run from it in practice as they arbitrage in the inefficiencies of programmatic”.
The Omnicom review now adds another layer of scrutiny for The Trade Desk, as holding companies reassess how ad tech partners charge for services and how much visibility clients have over those costs.