Put another way, SSPs are being cut out of deals as much as possible in the interest of supply-path optimization - which means more demand is flowing through OpenPath, TTD's direct connection to publishers. Oh, and TTD gets more revenue in the long run. But should all SSPs really be classified as resellers? Under the IAB's ads.txt spec , publishers can declare SSPs as either direct or indirect sellers of their ad inventory. And if the SSP is authorized as a direct seller in ads.txt, then it "is indeed a direct supply chain," according to Jounce . But a recent update to TTD's partner portal says: "We consider SSPs to be intermediaries because they are not a direct path to inventory." That's why, when a publisher sells inventory through an SSP and OpenPath, TTD's Kokai platform penalizes the SSP path and prioritizes OpenPath . TTD defends this approach by noting some SSPs take exorbitant cuts of publisher revenue and claiming that OpenPath funnels more money to pubs. But one anonymous source tells Digiday they've seen publisher payouts drop 50% as TTD directs more spend to OpenPath.
