Earlier this month, it made that reclassification official. 

On the surface, it sounds like semantics. But to SSPs — and the publishers relying on them — the reclassification comes with real consequences: less money and even less leverage.

The money part is straightforward. Kokai, The Trade Desk’s AI-powered platform, penalizes resold inventory and pushes toward what it calls “clean” supply paths. The leverage part is more existential. SSPs, already fighting for relevance, lose influence as buyers are pushed to go through The Trade Desk’s preferred integrations. 

“The Trade Desk is building sell-side functionality into its platform step-by-step and this latest move is already hitting the SSPs we work with,” said an ad exec who exchanged anonymity for candor. 

By itself, this doesn’t make The Trade Desk a villain. Fewer middlemen means fewer tricks — from bid duplication to floor manipulation — that can drain money from buyers. The issue is how it’s executed. The Trade Desk isn’t just cutting out inefficiencies — it’s using its position to tighten control over the flow of ad dollars. 

Here’s how that can — and often does — play out:

Take a publisher with inventory available through both an SSP and The Trade Desk’s preferred paths — OpenPath, its proprietary direct link to publishers, or SP500, a curated set of 500 “efficient” supply routes across the open exchange.

Before Kokai, where dollars landed often depended on buyer deals or preferred setups. Now, with SSPs tagged as resellers, those paths are scored as less efficient and lose out. Instead, Kokai steers more of the money toward OpenPath or SP500.

The Trade Desk frames this as a win-win: buyers get cleaner supply, sellers keep more net revenue. But The Trade Desk also wins, expanding its cut through OpenPath’s publisher fee and the monetization layers Kokai tacks on to SP500 buys, from bid shading to identity, measurement and third-party activations.

That’s the part that makes some companies uneasy.

“We’re seeing up to 50% reduction in publisher payouts through The Trade Desk since they started directing more spend through their own tool over the last quarter and a bit,” said an ad exec, who spoke on condition of anonymity over concerns they’d jeopardize the relationship.

The hit hasn’t been as severe for those with direct links to The Trade Desk’s dollars. Publishers and vendors plugged into its own supply routes — particularly OpenPath — are seeing more spend flow their way as a result. 

“We are seeing a marked increase in OpenPath spending,” said a publisher representative, who spoke to Digiday on condition of anonymity and didn’t provide exact figures.

Those without that access are left asking hard questions. 

“To be honest, we don’t have an OpenPath integration for me to test this, however, this may push us to get that path set up,” said the digital director of a publisher in North America, who spoke to Digiday on condition of anonymity.

Frustrating as this is for publishers and SSPs alike, it’s worth remembering the company isn’t acting out of malice so much as self-interest channeled through its clients. They’ve always been its north star, and in Kokai it’s found a way to translate their impatience with a marketplace littered with tricks and tolls into a system that doubles as leverage. Redefining who qualifies as a reseller feeds directly into that strategy. 

“We’re not against people making margin but we see a lot of crazy margin extraction in the marketplace that can be upwards of 60%,” said Will Doherty, svp of inventory development at The Trade Desk. ”We can’t fully rationalize that. Dynamic take rates, duplication, even ID bridging — these issues all create sub optimal variations and paths. When you have one path that is at a fixed fee and doesn’t do any of those things, it will often contrast favorably.”

All of this would be easier for critics to swallow if marketers could simply opt out and buy what they want, from whomever they want. They can’t. Exercising that control means digging through Kokai’s settings, or, more often, getting on the phone with a rep from The Trade Desk. In fairness, some of this is indicative of a platform still rolling out — quirks to fix, knobs for clients to learn. Even so, the friction makes clear where the leverage lies. 

“They’ve [The Trade Desk] redefined an industry-wide term so as to nudge buyers into spending more on their own products,” said an ad exec who spoke on condition of anonymity so as not to jeopardize commercial deals with ad tech firm. 

For ad execs like this, the move is triggering because it feels like deja vu. The Trade Desk once cast itself as the antidote to platform dominance. Now, they see it running the same playbook: a decade ago, publishers had to sell on Google’s terms or risk losing their biggest buyer; today they fear The Trade Desk is stepping into that role.

It’s a concern that’s been brewing for a while. 

As far back as 2022, when OpenPath launched, there were warnings that what was framed as an effort to bring clarity to a murky programmatic system could just as easily become a way to push more spend toward The Trade Desk. Those concerns have only intensified this year as more clients were moved onto Kokai, accelerating the flow of ad dollars away from some paths — and deeper into The Trade Desk’s own. 

“With OpenPath there’s no duplication, no dynamic rates or third-party parties that are in the supply chain,” said Doherty. “One of the harder things to deal with with some SSPs is that there’s often a lot of third parties in the transaction but because the SSP pays them directly they’re not declared.”