By Ronan Shields  •  March 27, 2025  •

Ivy Liu

Both sides defend their corners vehemently, with participants in the debate (seemingly) asking, ‘Is this necessary when Prebid exists?’

For some, supporting Trusted Server Framework will emancipate publishers from Big Tech – think web browsers from Apple and Google. However, for others, it could turn out to be a wolf in sheep’s clothing – think infrastructure providers like Amazon.

Trusted Server Framework proposals

According to IAB Tech Lab, the open-source project “shifts critical advertising functions away from the browser and into publisher-operated infrastructure.” This can be read as: “We’ll protect publishers from the policy whims of Apple and Google.” No reminders are needed here.

Anthony Katsur, IAB Tech Lab, CEO, said Trusted Server Framework can act as an alternative to the woes characterized by Chrome’s Privacy Sandbox. In particular, it will aid the preservation of first-party data signals and privacy compliance, plus mitigate publisher data leakage.

“Trusted Server flips the script,” he said in a press statement. “We’re giving power back to the publishers to run their own advertising middle layer, ensuring granular data control and security. This is a line in the sand. Either the digital media ecosystem takes control of its destiny or we watch the open web shrink even further.”

It further states that key features include:

• Server-side ad requests: Eliminates client-side dependencies and mitigates ad-blocking threats
• Prebid server integration: Executes programmatic auctions with existing supply-side partners
• Edge cloud processing: Securely captures and processes data signals
• Server-side ad stitching: Ensures first-party content experience and maintains monetization
• Faster web pages: Server-side processing lessens page bloat through fewer calls from the browser

The debate

The initiative was unveiled at IAB Tech Lab’s Signal Shift conference, where a Trusted Server Framework prototype was demonstrated. And it was here, as well as online, that intense debate on the matter arose.

Critics argued the prototype appeared naive or misguided, given that most server-side Prebid setups are run by SSPs, not publishers. They further argue adding more layers increases complexity and SSP control — outcomes at odds with IAB Tech Lab’s aims.

Furthermore, detractors argue the technical specifications on show would encourage other dubious actions, like bid caching, ID-bridging or miss-declarations. Worse still, it could open the door to fingerprinting – a major no-no for Big Tech providers.

IAB Tech Lab’s Katsur dismissed such assertions, highlighting that ad tech firms and publishers helped with development of the Trusted Server prototype. Speaking with Digiday, he further invited such critics to debate constructively via its Trusted Server task force.

Meanwhile, he counteracted assertions that the prototype’s current tech specifications leave Trusted Server Framework vulnerable to fingerprinting as overblown. This is primarily because “there is no legal definition of fingerprinting to our knowledge,” said Katsur.

He added, “Frankly, that identity module reflects what a lot of publishers do today when they append the HTTP user-agent and an IP-address to a first-party cookie. How is this any different?”

Others questioned if the tech specifications could result in tech providers, i.e., AWS’ content delivery network (CDN), controlling publisher monetization.

Gareth Glaser, cofounder of Gamera, and an influential blogger who advocates for publisher monetization, raised the prospect with Digiday. “This is not in the proposal but it alluded to this being a potential future,” he said. “Amazon [via its CDN within AWS] could auction the ads on websites before the websites even load.”

Glaser further advocated that publishers work with the Prebid server. “I don’t understand why we need all this hoopla.”

Katsur noted publishers’ woes with efforts in Privacy Sandbox, a scheme the standards body still supports. However, he added that while it may have discussed prototype developments with Big Tech players in its early development, i.e. its board members, Amazon in particular was “playing an active role in the solution.”

The debate continues. IAB Tech Lab has invited industry participants to its Trusted Server Framework task force, where such impassioned debates will continue. Further details will be confirmed in the coming quarter.

https://digiday.com/?p=573252