The Ad Supply Crunch Is Here. Publishers Need to Rethink Scarcity
Falling ad supply is starting to change the economics of the open web. For publishers, the opportunity is a chance to rebuild pricing power around quality, data and direct relationships.
Almost a year ago, while reviewing ad revenue, capacity and yield numbers across the Condé Nast portfolio, a steep decline in traffic, driven largely by Google’s AI Mode, pointed to one conclusion: a supply crunch was coming, and it would eventually push prices higher.
The logic was simple: Falling traffic means fewer pages viewed. Fewer pages viewed mean fewer ad slots loaded, and fewer ad slots loaded mean fewer impressions available to sell. If that decline continued across quality publishers while advertiser demand held steady, the open market would be left with less premium supply to bid on. Buyers would compete for a shrinking pool of quality impressions, and eCPMs would rise.
A fresh Ozone report, covering June 2026, now confirms the pattern. Across 20 billion impressions tracked in the UK and US, ad supply fell by roughly 40% year on year. UK eCPMs rose by around 30% year on year, while US eCPMs were up a more modest 7%. Bid density held steady at 5.4 bids per ad request, suggesting that demand has not fallen away. Buyers are still there. They are simply chasing fewer impressions, and paying more for the ones that remain.
Scarcity is new territory for programmatic
The open programmatic market was built on the assumption of abundant supply. RTB and the systems that sit around it were designed for large pools of impressions, and DSP bidding algorithms are tuned to work at scale. Scarcity changes the maths. Smaller sample sizes make optimisation harder and more costly, which means the buy side has its own reasons to be selective rather than simply chasing reach wherever it can be found.
That selectivity matters for publishers, because the reduction in supply is not evenly spread. Much of it is concentrated among the same top-tier titles that make up the premium end of the market, the kind of publishers now weighing up whether their best inventory, logged-in users, high-value formats, premium placements, belongs in the open marketplace at all.
Direct and programmatic guaranteed deals already account for more than three-quarters of US programmatic spend, according to eMarketer, and that share is likely to keep growing as sellers with strong direct sales operations decide the open auction no longer makes economic sense for their best inventory.
Why volume thinking will not solve this
The instinct for many yield teams will be to respond to falling ad requests with more of the same: adding ad units, chasing paid traffic, or leaning harder on lower-quality inventory to keep the numbers up. That is understandable, and it may help fill a Q4 budget gap, but it treats a structural shift as a short-term dip.
Buying traffic to compensate for falling supply is also becoming more expensive, since there are fewer users to buy, and it risks diluting the very quality signals that now command a premium.
The harder challenge may be cultural rather than technical. Publisher yield teams have spent years optimising for volume: pageviews, impressions, session length, all of it built on the logic that more traffic means more revenue. A market defined by scarcity asks for a different set of metrics: engagement and churn rather than pageviews, retention over raw traffic, lifetime value over RPM. That shift in mindset is arguably harder to make than the revenue loss itself.
As Gabriel Dorosz put it in Digiday’s coverage of the Ozone data, the opportunity now sits with publishers able to surface meaningful signals, whether first-party, contextual or attention-based, that demonstrate their impressions meet the quality thresholds buyers are actively seeking.
This points to where the real value lies: not in the auction price alone, but in proprietary data, direct audience relationships and formats a publisher’s competitors cannot easily replicate. Done well, this can also open other revenue lines, subscriptions, commerce, events, data licensing, that a purely volume-led model would never have prioritised.
Bottom Line
Publishers should not respond to falling supply by chasing volume, adding ad units or buying in lower-quality traffic to plug the gap. That approach treats a structural shift as a temporary problem and dilutes the inventory that is actually gaining value.
The better response is to make fewer, better impressions worth more: protecting premium supply for direct and guaranteed deals, proving inventory quality through first-party and contextual data, and building the audience relationships that give buyers a reason to pay above the average. A 40% drop in ad requests is not a quarter to manage through, but rather a clear signal to rebuild the business around scarcity rather than scale.
Mimmo Palmieri, AdTech & Data Monetisation Consultant
Mimmo Palmieri is an expert in advertising technology, AI, and data, and the founder of MIMMS, a sell-side consultancy that helps media brands unlock the full commercial value of their audiences and data, from ad tech infrastructure to first-party data strategies. He spent over a decade in senior global roles at Condé Nast and the Financial Times, leading advertising revenue, yield, measurement, and data functions. An Italian-born Londoner, Mimmo is a passionate builder, whether it’s digital products, global brands, or road bikes.