--- title: "Prebid’s Proposed Auction Overhaul Would Do What The Court Wouldn’t: Separate AdX From GAM" url: https://adtech.lol/articles/4e8803e8-b10b-4974-af9f-163c861ec985 source_url: https://www.adexchanger.com/programmatic/prebids-proposed-auction-overhaul-would-do-what-the-court-wouldnt-separate-adx-from-gam/ source_site: adexchanger author: "AdExchanger" published: 2026-10-14T00:45:00+00:00 tags: ["google", "Prebid", "ad server", "Google Ad Manager", "ad tech", "GAM", "ad exchange", "advertising"] publisher: AdTech Radar --- # Prebid’s Proposed Auction Overhaul Would Do What The Court Wouldn’t: Separate AdX From GAM > A federal court ordered Google to integrate with Prebid, spurring a proposal to change ad auction dynamics, allowing ad servers to bid into Prebid and seek to weaken Google Ad Manager's dominance. Last month, a federal court ordered Google to integrate with Prebid but didn’t say how. So Prebid is writing the instructions itself. The organization is moving ahead with a proposal to let ad servers bid into Prebid rather than Prebid bidding into ad servers, which is how Prebid auctions currently work. Prebid previewed this new auction model at the Prebid Summit in New York City on Tuesday. The proposed framework is currently in the public comment period, and the working group behind it hopes to have it formalized by the end of Q1, at which point it would be rolled out in a future Prebid update. The working group first pitched the proposal in April in anticipation of the possibility that Google could be forced to split up Google Ad Manager (GAM), which bundles the AdX ad exchange and its ad server, formerly known as DoubleClick for Publishers, into one product. As we now know, the court decided not to pursue a breakup of GAM as a remedy to Google’s ad tech monopoly. However, reorienting the ad auction so that ad servers bid into Prebid lets publishers access demand from Google AdX without also having to use Google’s ad server. In other words, it’s a way for Prebid to effectively unbundle GAM, even if the court decided not to. The change would also give Google a ready-made way to meet the Prebid integration requirement that Judge Leonie Brinkema mandated as part of the court’s remedies. But more importantly, it should make publishers less dependent on GAM while giving them more freedom to choose ad servers and run auctions in a way that benefits their business, according to Olly Burns, CTO at publisher monetization platform Teal and a co-author of the Prebid proposal, who spoke to AdExchanger in advance of the Prebid Summit. ## Making Google’s Prebid integration happen The court set three main requirements for how Google must work with Prebid. Google has to: - Let AdX demand bid into ad auctions independently of its ad server; - Integrate its ad server with Prebid independently via an API or other connection; - and share bid data, including winning and losing bids, with publishers. However, the court did not specify the mechanisms for enabling these connections between Google, Prebid, and publishers, Burns pointed out. Anticipating that lack of clarity, the Prebid working group proactively laid the groundwork for these integrations via Prebid Server. “We want Prebid to be on the front foot,” Burns said, “because if we can set the agenda, we can hopefully influence it to the good,” meaning for publishers. The working group also feared Google might not be a good-faith partner, according to Burns, who pointed to previous Google ad tech overhauls that went nowhere despite industrywide effort. “Google’s got a bit of a track record of screwing ad tech stuff up,” he said. “There’s been millions, if not billions, of pounds of investment in things like PAPI and all that sort of rubbish.” But, he added, if Prebid’s publisher community were to lead the charge instead, “we maximize the chance of success.” There’s a catch, though. Prebid can’t force Google to integrate through Prebid Server. Google could instead plug into Prebid.js, the browser-based version of Prebid for online display ads, said Brian Sardo, a senior software engineer at Microsoft, who led the Prebid Summit presentation of the proposal. The new auction framework is built for Prebid Server, so it only matters if Google goes that route. But Prebid is betting that Google will integrate with both Prebid Server and Prebid.js, according to Prebid members who spoke to AdExchanger at the Summit on background. Prebid is also betting that, if the framework for integration with Prebid Server is ready before the legal wrangling in Google’s antitrust case ends, Google is more likely to adopt it rather than building something from scratch. ## Taking the ‘pre’ out of ‘Prebid’ Having ad servers bid into Prebid would satisfy all three of the court’s requirements from the remedies because it makes Google’s auction happen alongside everyone else’s. The name “Prebid” itself is a relic of the past. Prebid was originally built to get around the auction constraints imposed by GAM, Burns said. Prebid would run a “pre auction,” he explained, and then feed the winning bids into the GAM auction, which is bundled with AdX, where Google’s ad auctions actually take place. But if ad servers, including GAM, can bid into Prebid, AdX will compete in the same auction as other SSPs. That means no more “pre auction” – which might require Prebid to change its name, Burns joked. ## Promoting competition Reorienting the auction in this way also removes one of Google’s key structural advantages. Under the old auction model, Prebid had to run its auction first, then send the winning bid into GAM to compete with Google’s AdX demand. That auction flow gave Google a look at the winning bid price of the Prebid auction, which allowed AdX demand to easily outbid the winning Prebid bidder, Burns said. Without that structural advantage, it will be interesting to see whether GAM becomes less of a dominant source of publisher revenue going forward, Constantine Mirin, CEO at Postindustria, told AdExchanger. Postindustria is a company that helps develop ad tech and fintech products, and it also participated in the working group that developed Prebid’s auction reorientation. Plus, with GAM and AdX bidding directly into Prebid, publishers get their court-mandated view into Google’s winning and losing bids, Mirin said. Previously, the only way for publishers to see how Google’s demand was bidding on their inventory was to use GAM. There’s a speed benefit, too. Publishers typically have to wait up to four hours for GAM analytics, Burns said, which means those insights aren’t valuable for responding to real-time market conditions. “If you plug in your own analytics stack, you can respond to market changes within a minute,” he added, “and in an open-auction environment, on a Black Friday, for example, that could be material.” On top of that, weakening GAM’s stranglehold on the ad server market – with GAM enjoying 90% market saturation, according to the Department of Justice – should promote more competition not just among ad servers, but also among solutions for analyzing bidding behavior. Once Prebid’s auction reorientation is in place, publishers will get far more flexibility to “plug in any analytics adapter,” including customizable dashboards that weigh more dimensions tailored to their business, said Eugene Dorfman, a technical partner and solutions architect at Postindustria and a co-author of the Prebid proposal. Not to mention that the model could also pave the way for “agentic-first ad servers,” Dorfman said, by making it easier for publishers to adopt them. And, finally, reorienting the auction should make the internet run faster, Burns said, because GAM is “one of the worst offenders in slowing the internet down.” Instead of a Prebid auction requiring two separate calls – one to Prebid and one to GAM – “we’re going to collapse it to one call, which pretty much halves the time,” he said. ## Next steps With the proposal currently in the comment period, there are still plenty of questions and concerns to be addressed by the Prebid community. For example, at the Prebid Summit, there was a healthy debate about the possibility of letting client-side (i.e., browser-based) Prebid auctions happen after the Prebid Server auction. That way, client-side bidders could react to the bids on the server side if they’re not also running a parallel Prebid Server auction. However, doing so would go against Prebid’s goal of making ad auctions work faster, argued Patrick McCann, SVP of research at Raptive and chair of Prebid.js. Plus, keeping auction decisioning on the server would prevent a publisher’s business logic from being exposed on the client side where browser companies can see it, Sardo said. And server-side decisioning also avoids the problem of publishers “chucking all your information over the wire in JSON,” said Hillary Slattery, senior director of product management, programmatic at the IAB Tech Lab. “You’re keeping it theoretically contained to parties that you trust enough to integrate with.” Importantly, though, there’s the wrinkle that adoption of the new auction framework hinges on Google bidding into Prebid Server in the first place, rather than only integrating into Prebid.js. But even with a federal court mandating that Google integrate with Prebid in some fashion, not every Prebid member in the room seemed convinced that Google will play ball. Looks like despite regulatory efforts to reduce its control over the wider ad tech ecosystem, Google still has plenty of weight to throw around. Source: [https://www.adexchanger.com/programmatic/prebids-proposed-auction-overhaul-would-do-what-the-court-wouldnt-separate-adx-from-gam/](https://www.adexchanger.com/programmatic/prebids-proposed-auction-overhaul-would-do-what-the-court-wouldnt-separate-adx-from-gam/)