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In the halcyon days of header bidding, publishers were delighted to integrate one demand source after another into their newly integrated wrappers. But even then many knew the shopping spree couldn’t last—the amount of duplicative auctions would eventually catch up with the buy side (causing immense pain to the DSPs, but hey—they had some good times during the waterfall age) and publishers would have to determine which partners boasted unique demand.
For the last few years, evaluating demand partners in headers has been a huge topic among publishers, inspiring a playbook and countless Publisher Forum sessions—there’s even one at PubForum Santa Monica, led by Hive Media’s Jennifer Chau and Azhar Salim focusing on A/B testing. Most publishers these days seem more focused on culling demand partners and supply path optimization than popping in Johnny-come-latelys.
Which is why I was surprised to see in the latest Jounce Media RTB Supply Path Benchmarking Report—available to those with Monstership subscriptions—that auction duplication was up over the past several months. Jounce’s research through always on-bidding of 61 publishers discovered that on average a publisher had 18.3 open-auction supply paths in January 2020, versus 17.8 in December and 17 in November.
I bet I wasn’t the only one who furrowed their brow at that stat. If publishers are weaning the header ranks and further pursuing supply path optimization, the number of duplicative auctions should be going down. Even if publishers added a few partners to take advantage of eager fourth-quarter spend, you’d think that would taper off in January.
But that got me wondering about some other research AdMonsters recently conducted on fill rates with GeoEdge. The final report found that while limiting partners in the header was a key way to reduce the probability of malvertising and redirects, more demand sources present created increased bid density and ultimately higher CPMs (and fill rates).
Especially in the open auction, it’s still in publishers’ interest to keep up high bid density via a large number of demand partners—which in turn results in duplicate auctions. This puts continuing pressure on the buy side to engage in supply path optimization—publishers aren’t lying when they point out the benefits for advertisers!
There’s even more amazing data in this month’s RTB Supply Path Benchmarking Report in the Monstership section. And you can also catch Jounce Media’s Chris Kane chat with the AdMonsters content team about the fate of the open programmatic ecosystem at Publisher Forum Santa Monica, March 8-11.