The role of Transaction ID (TID) in programmatic advertising has sparked intense debate among buyers, sellers, and technology intermediaries. The recent controversy centers on Prebid’s change that made TID non-unique across exchanges, undermining its purpose of helping buyers identify duplicate bid requests.
This update, rolled out quietly, raised concerns about governance and influence over open-source standards. On August 27, Ari Paparo, CEO of Marketecture Media, highlighted the issue on X, drawing widespread attention.
What is TID and why it matters
TID is part of the Prebid and OpenRTB standards and serves as a unique identifier linking multiple bid requests for the same impression back to a single auction. For buyers, especially demand-side platforms like The Trade Desk, it helps reduce duplicate bids and focuses spending on high-quality publishers.
Publishers and some supply-side platforms, however, see risks. Broad adoption could expose bid duplications that depress revenue, shift power toward buyers, and reduce publisher control over auctions.
The debate highlights a tension between improved auction efficiency for advertisers and fears among publishers that increased transparency will commoditize inventory and favor dominant buyers. The recent Prebid change, which restricts publisher choice on TID implementation, has intensified concerns about governance and standard-setting in the ecosystem.
Publisher concerns
Paul Bannister of Raptive warned that TID could erode publishers’ remaining control over data. He illustrated how a DSP could bypass publisher-set deal parameters by exploiting TID, undermining intended auction conditions. Bannister described this as potentially the “final nail in the coffin” for data control.
This view has resonated with many publishers skeptical that TID, while marketed as a transparency tool, may enable buyers to exploit data and weaken deal-based monetization.
Industry discourse
A recent Marketecture Podcast episode included a debate between Chris Kane of Jounce Media and Mike O’Sullivan of The Trade Desk, exposing sharply contrasting views:
- Chris Kane: Publishers fear revenue losses and buyer dominance via data leakage.
- Mike O’Sullivan: TID reduces auction waste, rewards quality publishers, and keeps the open web competitive against walled gardens.
Standards and governance concerns
Anthony Katsur, CEO of the IAB Tech Lab, warned on LinkedIn that Prebid’s move violates OpenRTB consistency, risking fragmentation of standards. He called for formal industry engagement to balance transparency with ecosystem stability.
Meanwhile, commentator Gareth Glaser expressed fatigue over recurring transparency disputes, noting the real issue is the deep mistrust between buyers and sellers masked by technical debates.
Implications
The TID debate illustrates a broader struggle over power in programmatic advertising. Buyers view TID as a tool to improve spend efficiency and transparency; publishers see it as reducing control and margins.
With Prebid’s recent changes and calls from the IAB Tech Lab for clearer governance, the industry faces a crossroads on whether it can establish a balanced standard respecting both transparency and publisher autonomy.
The ongoing discourse signals significant stakes for efficiency, fairness, and trust in digital advertising.