The Programmatic Supply Chain Is Being Forced to Name Everyone Who Touches a Bid Request

For the first time in the OpenRTB era, every company that touches a bid request will have to declare itself to buyers. IAB Tech Lab’s SupplyChain v1.1 proposal closes a disclosure gap that has let intermediaries remain invisible as long as they stayed out of the payment chain, and the $200 billion U.S. programmatic market will not look the same once it takes effect.

What the Current Standard Misses

The existing SupplyChain Object, commonly called “schain,” was designed to show buyers who gets paid in a programmatic transaction. That financial disclosure was a meaningful step when it launched, letting demand-side platforms perform supply-path optimization based on which SSPs and exchanges were collecting fees along a given bid request’s journey.

But the payment trail and the data trail are not the same thing. A bid request can pass through header bidding wrappers, ad servers, server-side ad insertion platforms, SDKs, and Prebid implementations before it reaches an exchange. Each of those nodes processes, routes, or enriches the request. None of them necessarily appears in the current schain if they do not receive a financial cut. The supply chain that buyers see has always been shorter than the supply chain that actually exists.

The result is a market that has struggled to answer a basic question: who, exactly, is handling publisher inventory before it reaches a buyer’s DSP? That question matters for supply-path optimization, for bid duplication, and for the kind of trust-based supply relationships that major advertisers want to build after years of transparency concerns in programmatic.

What SupplyChain v1.1 Changes

IAB Tech Lab announced SupplyChain v1.1 on June 23, 2026, with public comment open through August 21. The proposal extends the schain to cover three dimensions of every bid request: how it originated, who took technical custody of it at each step, and which parties participated in the payment flow. All three dimensions must now be disclosed.

The technical mechanism is the existing hp=0 designation, which marks a node as having taken custody of the request without participating in payment. Adding hp=0 nodes to the main schain record preserves backward compatibility with current systems while surfacing the full technical trail. Systems that must now declare themselves include SSPs and ad exchanges (already required under the current standard), Prebid implementations, ad servers, SSAI platforms, SDKs, and header bidding wrappers.

IAB Tech Lab and the proposal’s working group explicitly anticipate that supply chains will appear longer under v1.1. They frame that as a feature, not a bug. “This is one of the most significant transparency enhancements to the digital advertising supply chain in years,” said Anthony Katsur, CEO of IAB Tech Lab. “Advertisers deserve to understand not only who participates financially, but also who takes full control.”

The Trade Desk’s Rob Hazan, GM of Product Management, made the counter-intuitive point explicit: “A longer chain that accurately discloses the parties involved is better than a short chain hiding information. Longer supply chains are not automatically worse supply chains.” The logic is that a disclosed intermediary is one that can be evaluated on its merits, while an invisible intermediary is one that cannot.

Who Faces Pressure and Who Benefits

For intermediaries that add genuine value — a targeting layer, an audience enrichment step, a supply-side integration that improves fill rates — visibility is a competitive advantage. v1.1 gives those companies a way to show buyers what they actually do in the transaction chain, not just whether they appeared on a payment ledger.

The pressure falls on intermediaries that have operated as pass-through nodes: routing or processing bid requests without adding discernible capability or margin. When buyers can see every entity that touched a request, supply-path optimization can for the first time account for technical custody as well as financial custody. Low-value nodes that have persisted because they were invisible will now be visible, and demand-side teams that take SPO seriously will deprioritize them.

Neal Richter, VP at Amazon Ads and Chair of the IAB Tech Lab Board of Directors, summed up the buyer-side logic: “This update is an important step forward because it gives buyers clearer understanding of how supply is actually created.” Endorsing organizations at launch include Amazon Ads, The Trade Desk, Raptive, and Jounce Media.

Bid request duplication is a related beneficiary. When the same publisher impression is bid on multiple times through different intermediary chains, v1.1 makes those chains comparable at the technical level. Buyers and DSPs will gain the inputs to identify and deprioritize redundant paths in a way the current standard does not support.

What This Means for the Marketing Leader

For marketing and media buying leaders, SupplyChain v1.1 reshapes what supply-path optimization means in practice. SPO has focused primarily on reducing financial hops: fewer SSPs, shorter payment chains, lower take rates. v1.1 adds a second axis, the technical custody path, and makes the two comparable for the first time.

That changes the conversation with agency trading desks and DSP partners. Today, a “clean” supply path typically means fewer financial intermediaries. Under v1.1, clean will also mean fewer technical intermediaries with clear value attribution at each step. Marketing leaders should expect their agency partners to incorporate expanded schain data into SPO decision-making once adoption begins, and those conversations will be more granular than the current fee-based discussions.

The broader implication is for vendor accountability across the programmatic stack. Independent DSPs and SSPs have consolidated significantly over the past several years as buyers concentrated spend on fewer, more transparent partners. v1.1 provides additional data to continue that consolidation, now applied to the technical custody layer that the current standard has left opaque.

How to Engage Before August 21

The comment period closes August 21, 2026. Organizations that rely on SSAI, header bidding wrappers, or custom SDK implementations should audit their current schain disclosures against v1.1 requirements before the standard is finalized. The working group expects a staged rollout coordinating SSP and DSP testing after the comment period closes.

For buyers and brands, the near-term action is to ask DSP and agency partners how they plan to incorporate expanded schain data into SPO reporting. The proposal is not yet final, but the direction is unlikely to change materially. Marketing leaders who understand the technical custody layer before v1.1 takes effect will be better positioned to hold supply-chain partners accountable when it does.

Programmatic advertising has operated with partial supply chain visibility since OpenRTB launched. SupplyChain v1.1 does not solve every accountability problem in the ecosystem. But it closes a specific and consequential gap that has let non-transparent intermediaries persist for a decade, and it hands buyers the data to act on it.

Source: IAB Tech Lab / PR Newswire