The recent leaked memo from Publicis Groupe has sent the advertising industry into a flurry of memes, watercooler conversations, and widespread reflection on the future of advertising spend. 

Perhaps the real conversation should be focused on transparency, and how certain programmatic buying models might be masking the true cost of media. Following the decisions by giants like Publicis, dentsu, and WPP to rethink their relationship with The Trade Desk (TTD), we spoke with Robin LeGassicke from Cairns Oneil to cut through the noise. 

We discussed why TTD's push for transparency—specifically through tools like OpenPath—might actually be threatening the principal-based buying revenues that some agencies rely on. Robin shares Cairns Oneil's approach to an agnostic, fully transparent model , shedding light on the hidden rebates in the supply chain and why the Open Web is far from dead.

Does your agency have an official stance on its relationship with The Trade Desk?

We operate within an agnostic model that demands transparency.  Models that rely on principal-based buying will increase fees across the entire supply chain, and when you want to have a fully transparent model, principal-based or commercial agreements with SSPs will no longer be an option. The TTD openpath puts this practice at risk for companies that generate revenue through principal-based buying.

At Cairns Oneil, we believe in full transparency and are committed to building a martech ecosystem that delivers on this promise. We design our solutions to be transparent and neutral, allowing us to leverage the best technology partners to drive the outcomes our clients need.

There is more transparency currently in the buy side, as agencies and brands do have greater control over that. 

Buy-side platforms (DSPs) – Tech fees, Ad serving, margins, media/publisher costs are easier to have full transparency as you build out your contracts and agreements with each DSP you contract. 

Sell-side platforms (SSPs) also have built-in fees, but transparency around these costs is limited. In theory, we should be able to see and understand them. In practice, each SSP connects to publishers and DSPs differently, creating multiple layers and opportunities to obscure rebates, volume agreements, and additional fees. 

Agencies typically have contractual agreements with SSPs to secure volume discounts or rebates, which may or may not be passed back to clients. Even with these agreements in place, there is still limited transparency across the supply chain.

What does this move by Publicis signal to the industry?

We have always viewed TTD’s products as being built for transparency, and their recent statements continue to emphasize this and reinforce their positioning. As they evolve their platform and add features to serve a wider range of users—including agencies and brands—agencies are able to increasingly benefit from it. All users retain the option to allocate spend to any available DSPs as they see fit for their objectives.

What remains concerning for the industry are non-transparent practices that are not disclosed to brands, such as principal-based buying, arbitrage, volume agreements, and other commercial incentives that are not communicated to clients. We still hear about and see these practices across the media buying ecosystem.

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