Supply-side targeting no longer sits at the edges of connected TV. OpenX’s first supply-side intelligence report, released October 15, 2026, says SST captured 51% of CTV deal spend on its U.S. marketplace in 2025, up from 9% in 2022. Third-party audience data moved the other way, falling from 78% of SST spend to roughly 40%.
Why the balance moved to the seller side
OpenX runs a marketplace where publishers and streaming apps sell inventory. The report argues that buyers are increasingly applying audience, quality, measurement and algorithmic signals on that side of the transaction, rather than only inside demand-side platforms. Connected TV is the strongest example because streaming has no browser cookie and household-level signals are fragmented across TV makers, operating systems and apps.
OpenX points to privacy pressure as the catalyst. Google’s initial 1% Chrome cookie test in January 2024, Apple’s App Tracking Transparency and state and EU privacy rules convinced buyers that signal loss would keep building. As the report puts it, “signal loss would only get worse, not better.” On CTV, content objects — metadata like title, genre, episode and rating — became the practical replacement. OpenX says quality targeting hit 35% of all U.S. SST spend in 2025, pulled overwhelmingly by CTV.
Read the taxonomy before you benchmark
These numbers come from OpenX’s own transaction records, sorted under rules OpenX wrote. The most consequential rule: when a deal mixes several signals, OpenX classifies it by the “most advanced” method. A basic site list with one third-party segment bolted on could count fully as SST. That means part of the shift away from third-party data may reflect classification precedence rather than a change in what buyers actually bought.
The report also stops short of a dollar base. It gives shares and growth rates, never the size of the market beneath them. The CTV story contains two year-end figures too: 51% appears three times, while a later section says 53%. The chart’s quarterly numbers average about 51%, by PPC Land’s reading.
What to do with this
- Split share from spend. A rising share can hide an expanding base; ask for absolute trends and the deal sample before benchmarking.
- Probe the classification. If mixed deals are counted by the most advanced signal, ask what ranks above what in your SSP’s taxonomy.
- Test content-object CTV tiers. Genre, show and rating metadata is the fastest-moving lever, but only 40% of CTV bid requests carried usable program-level signals in Peer39’s March 2026 check.
The buy-side voices are all OpenX clients
The qualitative research rests on eight one-on-one interviews with senior buy-side executives: seven from media agencies and one from a Fortune 50 brand. All are OpenX clients, the report says. Quoted buyers describe moving more targeting logic out of the DSP and into the SSP. Stagwell’s Chris Milano argues that applying data on the SSP gives better fidelity because it sits closer to the publisher. Polaris’ Audrey Elman says tools she once went to a DSP for she now goes “straight to an SSP” for.
That is directionally useful, but it is not a neutral sample. Buyers who tested the approach and walked away are absent, so treat the quotes as a view from adopters, not proof of market consensus.
The clear takeaway for CTV teams: the supply side is becoming a strategic targeting layer. The open question is how much of this is real buying change and how much is taxonomy.
Source: PPC Land
