Programmatic Advertising: Why Is Financial Transparency Still So Difficult?

By Max Legrand · GreyFox Ads · Insights from the French programmatic market

“When I spend €1,000 on Google or Meta, at least I feel I know where the money goes. In programmatic? It is still a complete mystery.” That is how an advertiser described their frustration to me. And the uncomfortable part is that the industry has been discussing this problem for years.

1. Financial opacity in programmatic is not a new problem

Back in 2015, French newspaper Les Echos described programmatic as a revolutionary but opaque advertising tool. Nearly a decade later, transparency was still a live topic in the French market, including in discussions involving Nestlé, WPP Media and Hubvisor reported by journalist Nicolas Jaimes.

One figure mentioned in that debate was 13% of advertising budgets that could not be fully accounted for in the reported reconciliation exercise (the precise scope, methodology and definition of the gap matter; it should not be interpreted as a universal fee or loss rate across all programmatic campaigns).

So why has an industry built on data and measurement struggled for so long to explain the path of an advertising euro?

2. Where does an advertiser's programmatic budget actually go?

A single impression can involve an agency, a demand-side platform (DSP), verification or data providers, an exchange or supply-side platform (SSP), additional intermediaries and finally the publisher. Each partner may provide a legitimate service. The difficulty begins when the buyer cannot see which partners were involved and what each charged.

This is a simplified map: not every impression passes through every layer, and contractual arrangements vary. But the fundamental question remains the same: can the advertiser reconcile what they paid with what the publisher received?

3. Why reseller chains can make transparency harder

When publisher monetization becomes difficult, adding more demand connections can appear attractive. Header Bidding made it easier to connect several SSPs, while reseller arrangements created additional routes to the same inventory.

That does not mean every reseller is unnecessary. Some provide real incremental demand, technical capabilities or market access. But additional hops can also introduce fees, duplicate auction paths and less visibility over the final seller.

This is why understanding the role of resellers in programmatic bid requests matters, and why the industry invests in Supply Path Optimization (SPO). Our guide to ads.txt and DIRECT versus RESELLER explains one of the public signals buyers can use to investigate supply relationships (although ads.txt alone does not reveal the full commercial fee chain).

4. Trust ID: a French attempt to reconcile the money flow

Here in France, Alliance Digitale, the SRI (Syndicat des Régies Internet) and Union des marques were involved in the Trust ID transparency initiative, tested around 2020.

The idea was to use an identifier collected through a pixel in the advertising creative to help the buying and selling sides match impressions and compare their respective records. Rather than debating transparency in the abstract, participants could investigate the difference between amounts recorded on either side of a transaction.

The project did not become a widely adopted industry standard. The original post does not establish a definitive reason for that limited adoption, so it would be misleading to assign one without further evidence. What it illustrates, however, is how much coordination is required between advertisers, agencies, platforms and publishers to achieve meaningful reconciliation.

5. A crucial distinction: disclosed fees versus unexplained discrepancies

When people say money has “disappeared” in programmatic, they may be referring to different things. They should not be lumped together.

Not every discrepancy is evidence of fraud or hidden margin. Reporting definitions, auction mechanics, currency conversion, measurement timing and contractual boundaries can all affect reconciliation (which is why like-for-like datasets are essential).

6. What can Media Traders and advertisers do?

Financial transparency improves when buyers make it a practical buying requirement rather than a slogan.

• Map the supply chain: identify the DSP, SSP, seller and any intermediate resellers for the inventory you buy.
• Ask for itemized fees: separate media, technology, data and verification charges wherever the commercial model allows.
• Prefer explainable supply paths: use sellers.json, ads.txt and supply-chain signals alongside contractual information.
• Compare buyer and publisher records: reconcile impressions and spend on a consistent scope, rather than assuming both systems measure identical things.
• Evaluate performance as well as price: a cheaper path is not automatically the most effective one if inventory quality or outcomes deteriorate.

For related practical context, see our explanation of Transaction IDs and auction-path transparency and our analysis of how restrictive quality filters reshape the available French Open Web inventory.

7. Why GreyFox Ads puts transparency into its curated deals

At GreyFox Ads, we believe that the quality Open Web deserves a business model buyers can understand. We build curated programmatic deals for the French market with an emphasis on quality inventory, more direct publisher supply paths and clear visibility into the chain of costs.

For international Media Traders managing French campaigns, our Master Deal combines local market expertise, quality controls and simplified activation through a single curated deal. The goal is not to pretend that programmatic has no costs. It is to make those costs understandable and justify them through the value delivered.

Because when you buy a service, knowing what it actually costs should be perfectly normal.

Original perspective: Read the original LinkedIn post. Historical references and figures above reflect the author's original post and have not been independently audited for this adaptation.