OpenX today released a Supply-Side Intelligence Trend Report claiming that spend using supply-side targeting on its exchange doubled year-over-year in 2025, and that the share of spend applying the technique rose from 11% in the fourth quarter of 2023 to 37% two years later. The figures come from OpenX's own transaction data, have not been independently verified, and arrive from a company that sells the very product category the report describes.

In Short

OpenX, a company that runs an ad exchange where websites and streaming apps sell ad space, published numbers showing that more advertisers are using audience and quality data at the selling end of the auction before they bid. That matters to agencies and brands because it suggests a growing share of their programmatic budget is shaped by tools the seller controls, not only by the buying platform they log into. The catch is that every number comes from OpenX, about OpenX, and the full methodology was not part of what OpenX released today.

What OpenX released

The announcement, datelined New York, October 15, 2026, carries the headline "Supply-Side Targeting Spend Doubles as Buyers Move Beyond Inventory Curation." According to OpenX, the report draws on three years of U.S. transaction data, regional comparisons with EMEA, and interviews with eight senior buy-side executives. The company describes itself in the release as "The Intelligent SSP," a brand position it adopted in April 2026.

OpenX's central claim is definitional as much as statistical. According to the company, the report separates three ideas that the trade often blurs together. Supply-side intelligence is defined as tools within an SSP that help buyers choose better inventory, improve campaign performance and streamline workflows. Curation is defined more narrowly as inventory selection, such as choosing sites and setting viewability requirements. Supply-side targeting, abbreviated SST throughout the release, "goes further," according to OpenX, by using audience data, quality signals and predictive models to guide buying decisions.

That distinction is not neutral. Across 2025 and 2026, curation became one of the most contested words in programmatic advertising, with sell-side platforms packaging inventory and data into deals and buy-side platforms questioning the fees embedded in those packages. By drawing a line between curation and SST, OpenX positions its own offering as something more than packaging. According to the release, buyers "benefit from assessing those capabilities directly, rather than treating all supply-side activation as 'curation.'"

The four numbers

OpenX highlights four findings. Each is vendor-supplied, and each deserves a closer reading than the release gives it.

Share of spend: 11%, 19%, 37%

According to OpenX, the share of spend using SST was 11% in Q4 2023, 19% a year later and 37% a year after that, which places the most recent figure in Q4 2025. The company summarises the trend as SST spend "growing ~2x annually." The share figures support that description: 11% to 19% is an increase of roughly 73%, and 19% to 37% is roughly 95%.

What the release does not specify is the denominator. "Share of spend" almost certainly means share of spend transacting through OpenX, not share of all U.S. programmatic spend, but the text never says so explicitly. Nor does it give a dollar figure for SST spend in any period, which means the headline claim that "SST spend doubled year-over-year in 2025" cannot be checked against the share data. A doubling in share and a doubling in absolute spend are only the same thing if total spend on the exchange stayed flat.

Measurement in 17% of deals

According to OpenX, 17% of deals in 2025 included measurement used to build and validate audiences using real-world outcomes. The company presents this as "signaling a shift beyond digital proxy metrics toward connecting ad exposure with physical behaviors and offline actions."

The release does not name the measurement providers involved, define what counts as a real-world outcome, or say whether deals are counted by number or weighted by spend. A deal that ran a single small test and a deal carrying a large share of a brand's annual budget would each count once under a simple deal count. There is also no comparison year, so the release does not show whether 17% is up, down or flat.

CTV: 500% growth over three years

According to OpenX, CTV spend using SST grew 500% between H1 2022 and H1 2025, "as buyers make greater use of content signals such as genre and rating to identify relevant inventory." That figure covers a different window from the other findings. It starts in the first half of 2022, ends in the first half of 2025, and so does not include the second half of 2025, the period in which the company says overall SST spend doubled.

A 500% increase means the H1 2025 figure was six times the H1 2022 figure. Without a starting value, it is impossible to tell whether that represents a small base growing quickly or a meaningful category shift. The release gives no CTV share figure comparable to the 37% headline.

U.S. and EMEA: about 11% a quarter

The fourth finding is that SST grew at roughly 11% a quarter on average in both the U.S. and EMEA since Q1 2025. According to OpenX, that indicates "sustained momentum and growth across both markets."

There is an arithmetic tension worth flagging here. Compounded over four quarters, 11% quarterly growth produces roughly 52% annual growth, not the doubling the release describes for 2025. The two figures may measure different things, one perhaps a share and the other a dollar amount, or they may cover different periods, since the quarterly figure runs from Q1 2025 while the doubling is described year-over-year. The release does not reconcile them, and PPC Land did not receive the full report against which to check.

What the release leaves out

The press materials sent to PPC Land consisted of the release text; the full report was referenced as an attachment and a link but was not part of the documents reviewed for this article. Several things a buyer would want before relying on the figures are therefore missing from what OpenX published today:

  • Methodology. There is no description of how OpenX classified a transaction as SST rather than curation, which is the distinction on which the entire report rests.
  • Sample size. The release says "three years of U.S. transaction data" without a volume of impressions, dollars, deals or buyers.
  • EMEA scope. The regional comparison does not say which countries are included or how EMEA data was weighted.
  • Interview selection. Eight senior buy-side executives were interviewed. Only one, Chris Milano of Stagwell Media, is named and quoted. The release does not say how the eight were chosen or whether they are OpenX customers.
  • Access and pricing. The report is described as available via a link, with no indication of whether it is gated behind a registration form. OpenX says nothing about pricing for the SST tools themselves.

The most significant omission is a conflict that the release does not address. OpenX sells supply-side targeting. In July 2025 the company made OpenXSelect, its curation and supply-side targeting platform, generally available to agencies and brands. Growth in SST share on OpenX's exchange since then is, at least in part, a measure of adoption of OpenX's own product, and a report built on that data is not an independent read of the market.

The quotes

Two people are quoted in the release. Chris Milano, Global VP of Supply at Stagwell Media, is the only buyer named: "It just makes sense that you would get better data fidelity by working closer to the publisher. So it makes sense to apply data on the SSP whenever possible."

Tyler Romasco, EVP, Commercial at OpenX, frames the findings in the company's terms. "The doubling of spend in 2025 shows that buyers increasingly understand the need to work more closely with SSPs," Romasco said, according to the release. "Buyers see real value in the data that lives closest to the impression and in the decisioning that can happen on the supply side. When intelligence gets applied earlier in the process, buyers get better results, and publishers get more value from their inventory."

Neither quote offers a performance figure. The phrase "better results" is not attached to any metric in the release, and the claim that the report "proves" buyers benefit from assessing capabilities directly is OpenX's own characterisation of its findings.

How OpenX got here

The report fits a pattern visible in OpenX's announcements over the past fifteen months, each of which pushed the company further from a pure auction operator toward a seller of data and decisioning.

According to the release, OpenX is "building on its legacy in identity solutions." The company's people-based OpenAudience platform dates to 2018, and its identity graph was cited at 237 million U.S. users and 150 million CTV devices in July 2025. When OpenXSelect launched that month, OpenX claimed self-service partners cut campaign setup and optimization time by up to 50% and achieved up to 2x the reach of previous methods, figures that were also company-supplied.

In January 2026, OpenX unveiled OpenXBuild, a suite of three APIs for Real-Time Bidstream, Identity Resolution and Auction Insights, letting buyers shape bidding strategies before auctions run. Early adopter tvScientific reported a 70% drop in cost-per-conversion on OpenX traffic compared with unshaped inventory. In March 2026, OpenX and TVision brought real-time attention targeting to CTV buyers, a pre-bid capability available only through OpenXSelect. That launch is directly relevant to today's CTV figure: it is the kind of content-and-attention signal the release credits for the 500% CTV growth, though the March launch postdates the H1 2022 to H1 2025 window.

On April 13, 2026, OpenX adopted the "Intelligent SSP" positioning, shifting away from earlier emphasis on transparency and sustainability. In September 2026, OpenX claimed it processes 3 million queries per second with partner decisioning logic running inside its auction in roughly 5 milliseconds, again without third-party verification. And on October 5, 2026, OpenX became the launch partner for HUMAN Security's Ad Integrity Suite for Platforms, which passes invalid traffic, viewability and brand safety signals to DSPs and SSPs.

Read together, those announcements explain the report's framing. Quality signals, audience data and predictive models, the three components OpenX uses to define SST, map closely onto products it has shipped or partnered on since mid-2025.

Why this matters for buyers and publishers

The underlying argument is about where decisions happen in a programmatic transaction. In the conventional model, a supply-side platform runs the auction on behalf of publishers while the buyer's DSP applies audience data and bidding logic. Supply-side targeting moves some of that logic upstream, so that by the time a bid request reaches the buyer, it has already been filtered or enriched by the seller's platform, usually packaged as a deal ID the buyer targets.

PPC Land has tracked that migration from several directions. Germany's BVDW published a whitepaper in February 2026 that defined curation as "targeted selection, combination and enrichment" of inventory and data, placing it mainly on the sell side and identifying four types of curators. Magnite brought 200 petabytes of Expedia traveler data into its supply-side pipes in April 2026, activated through curated deal IDs that are DSP-agnostic. And Microsoft packaged LinkedIn profile data into CTV deals through Microsoft Monetize in May 2026, with a $50,000 minimum over 30 days.

Each of those moves puts data at the sell side and asks the buyer to trust the packaging. The commercial tension is that sell-side fees are frequently built into the deal price rather than itemised. A buyer who sees a deal ID clearing at a given CPM may not see how much of that price is media and how much is data or decisioning. OpenX's report does not address fees, take rates or price at all.

For CTV in particular, the claim that buyers are using genre and rating signals at the supply side is plausible given that streaming inventory often arrives without the cookie-based audience signals available on the open web. Yet the content-signal argument also cuts the other way. In August 2026 The Trade Desk gained show-level CTV data from Gracenote, bringing comparable signals into the buy side. Whether buyers apply those signals in the SSP or the DSP is precisely the contest the report is trying to settle in OpenX's favour.

Is 37% a meaningful number? Within OpenX's marketplace, if the figure is accurate and the classification is sound, it indicates that more than a third of the spend flowing through one of the larger independent SSPs is now shaped by seller-side data and models. That is a material change from 11% two years earlier. Outside OpenX, the report offers no evidence either way. The release offers no comparison with rival SSPs, and OpenX's numbers cannot stand in for the market.

OpenX is also a party in a follow-on antitrust suit against Google, filed in the Eastern District of Virginia on August 4, 2025, seeking treble damages over alleged tying and auction manipulation. That case and today's report are unrelated in substance, but both reflect a company arguing that the value in programmatic advertising should sit with independent sell-side infrastructure rather than with the largest platforms.

Timeline

Summary

Who: OpenX, the Pasadena-based independent supply-side platform that markets itself as "The Intelligent SSP," with quotes from Tyler Romasco, EVP, Commercial at OpenX, and Chris Milano, Global VP of Supply at Stagwell Media.

What: A Supply-Side Intelligence Trend Report claiming that supply-side targeting reached 37% of spend in Q4 2025, up from 11% in Q4 2023; that 17% of 2025 deals included real-world outcome measurement; that CTV spend using SST grew 500% between H1 2022 and H1 2025; and that SST grew about 11% a quarter in the U.S. and EMEA since Q1 2025. All figures are vendor-supplied, drawn from OpenX's own transaction data, with no published methodology, sample size or dollar values.

When: The report was released today, October 15, 2026. Its data spans H1 2022 to Q4 2025.

Where: U.S. transaction data with regional comparisons to EMEA, announced from New York.

Why: OpenX is arguing that SSPs add value beyond packaging inventory, and that buyers should judge supply-side tools by their audience data, quality signals and models rather than lumping them together as curation. The report measures, in part, adoption of OpenX's own OpenXSelect product, and it does not address the fees buyers pay for supply-side data.