Dive Brief:
- More brand marketers are worrying over principal media, when ad agencies act as both the principal buyer and reseller of media, but only 57% have governance guidelines over the practice, according to a new report from the Association of National Advertisers.
- Among client-side marketers surveyed by the trade body, 90% cite uncertainty that principal media is in their best interest as a top concern. That’s up from 79% who said the same in 2024, when the ANA began analyzing principal media in greater detail.
- More than one-third of surveyed marketers said their contracts with agencies do not address principal media or they were otherwise unsure on the matter. The group’s research and advice for navigating principal media follows increased scrutiny into the space, with fresh questions over whether agencies keep media rebates received from publishers.
Dive Insight:
Principal media has become a bigger focus for media agencies, particularly large ones within ad-holding groups that transact substantial publisher deals. The practice entails agencies purchasing media, becoming its principal owner, and then reselling it to their clients rather than exclusively acting as buying agents on the clients’ behalf. Even as principal media is growing more common in advertising, brand marketers are encountering significant knowledge gaps, with many not implementing thorough governance and some being unsure of whether their agency agreements account for the practice in the first place.
The ANA shared several tips for marketers looking to tackle the problem, including: introducing a more rigorous approval process; ironing out contracts to specifically address any uses of principal media (for example: forbidding principal buys to be intermingled with standard agent-led buys); setting caps on the amount of budget that can be allotted to the category and ensuring a clear window into the outlets where principal media deals are applied. In addition, the trade body recommended clients push their agencies to lay out concrete business use cases for pursuing principal media in lieu of alternatives, inclusive of cost and audience delivery comparisons with standard agent-led media buys.
“Principal media is becoming a more common part of the media ecosystem, but marketers need to ensure they have the right safeguards in place,” said ANA CEO Bob Liodice, in a statement attached to the report. “For our members, that starts with making sure agency contracts explicitly address principal media and establishing clear internal approval processes. Marketers should always understand whether their agency is acting as an agent or a principal in any media transaction.”
Principal media can be a valuable profit-driver for agencies but has amplified long-standing transparency concerns, with renewed controversy over rebates, wherein agencies pocket the benefits of hitting certain spending thresholds with publishers even though they accomplished those goals using a client’s advertising budget. The media rebate issue — a poorly kept secret that clients and agencies have frequently butted heads over — is at the center of a current lawsuit against WPP Media by a former employee, who alleges he was fired from the company for calling out rebates that were not properly disclosed to clients.
Several factors are contributing to the broader uptick in principal media, including mounting pressure on publicly traded holding companies to demonstrate financial performance. Building on that, industry consolidation is accelerating the trend, per the ANA.
Omnicom’s $13 billion-plus acquisition of rival Interpublic Group last year, which has created the world’s largest marketing services organization and mashed together two already massive media operations, has “significantly expanded the scale and strategic importance” of principal-based media buying, the ANA wrote in the report. Omnicom has estimated its media and advertising segment could grow between 50% and 60% with the addition of IPG’s assets.
“Increased scale changes the economics of media buying, making it more practical for agencies to purchase inventory in larger volumes and deploy it across multiple clients,” the ANA report reads. “In that context, principal-based trading becomes more scalable and financially attractive.”
Seventy-six percent of marketers see cost reductions as the chief benefit of principal-based media buying, the ANA found. Proliferation of principal media is reflected elsewhere in the ANA survey findings, with 56% of marketers expecting to use principal media this year versus 41% who said the same in the 2024 study. Similarly, 37% have seen their principal media usage jump in the past year, compared to 24% who said so previously.
The ANA surveyed 114 client-side marketers between Oct. 10 and Dec. 19 of 2025 to gather its findings. A majority of respondents, 81%, held director-level or higher positions.
