The trend: Supply-side platforms (SSPs) are offering access to publisher data that demand-side platforms (DSPs) can’t, and ad buyers are welcoming the shift.

Data from several independent SSPs paints the picture:

• In Q2 2026, ad spend for PubMatic Activate—which connects buyers directly to publisher-side infrastructure—more than doubled YoY, per an earnings report.
• Index Exchange’s top 100 media owners saw 53% higher eCPMs by using its sell-side intelligence platform, per a company blog post.
• The share of deals made on OpenX that used supply-side targeting (SST) nearly doubled YoY in 2025, accounting for 37% of all spend, per a new report.

This activity reflects an appetite from ad buyers to seal gaps in their SSP strategies. While US and UK advertisers ranked inventory quality as the top factor for campaign success, they also said performance inconsistency was their biggest frustration, per a report from SSP TripleLift.

Why it matters: SSPs are playing a larger role in ad buying because they can bring advertisers closer to the content in which they’ll appear. These platforms work directly with publishers, and if they can help demystify more aspects of publisher content, such as quality and content characteristics, ad buyers are better able to make informed decisions.

Meanwhile, signal loss has compelled ad buyers to move more spend to walled gardens. Open-web SSPs are hoping to reverse this trend by improving insights like targeting—which US and UK marketers say is their primary inhibition when it comes to open-web spending, per Taboola.

SSPs are also courting other players in the programmatic ecosystem to strengthen their insights. Index Exchange, which pitched its intelligence hub at Advertising Week earlier this month, is teaming with DSPs like Bedrock to bring more bidding-related data into one place. The rise of SSPs as providers of intelligence, not just inventory, reflects a shifting competitive map in the programmatic space.

Recommendations for ad buyers: Lean into SSPs as data partners to gain richer inventory insights, but don’t neglect DSP data.

• Reduce curation-only deals (which focus solely on inventory selection) to open up more room to incorporate supply-side intelligence.
• Use supply-side intelligence to gain a better understanding of content quality, but experiment with emerging AI capabilities to see whether SSPs can also help predict better ad buying.
• Combine SSPs’ inventory-focused data with DSPs’ audience-focused data to maximize buying clarity.

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