TL;DR: Agent-to-agent deal reconciliation works from the DealSheet outward. Both parties agreed the terms before any impression was served; the DealSheet is the shared reference point. Reconciliation is a comparison of delivery data against that shared reference, not a comparison of two separate logs produced by different systems. Discrepancies are identified against a document both parties hold, which eliminates the version ambiguity that makes conventional programmatic reconciliation difficult.
Post-campaign reconciliation is one of the most persistent operational problems in programmatic advertising. A buyer's impression log and a publisher's delivery log are produced by different systems using different counting methodologies. They diverge routinely. The industry has built an entire credits and adjustments process to manage this divergence, but it is slow, dispute-prone, and expensive to run at scale.
The source of the problem is structural. In conventional programmatic, the deal terms are not captured in a single authoritative document before the campaign runs. The buyer's DSP holds the buyer's view of the deal. The publisher's SSP holds the publisher's view. These are separate records created by separate systems. When delivery data is compared after the campaign, neither party has a shared reference point.
Agent-to-agent deal reconciliation addresses this at the point of deal creation.
The DealSheet as the reconciliation anchor
When a buy-side agent and a sell-side agent reach agreement, the terms are written to a bilateral deal record, the DealSheet, before any impression is served. The DealSheet captures the agreed CPM, the inventory scope, the audience data conditions, the campaign period, and the delivery commitment. Both parties hold this record in shared state: the buy-side agent's principal can access it, and the sell-side agent's principal can access it. Neither party holds a different version.
Reconciliation, after the campaign runs, begins with this shared document. The buyer compares their delivery data against the DealSheet terms. The publisher compares their delivery data against the same DealSheet terms. If both sets of delivery data match the DealSheet, reconciliation is clean. If there is a discrepancy between what was delivered and what was agreed, it is immediately visible in the delivery data, with the DealSheet as the unambiguous reference.
This eliminates the first source of conventional programmatic reconciliation disputes: the version problem, where the buyer and publisher are arguing about terms because they each have a different document that they believe is the authoritative record.
Where discrepancies still arise
A shared deal record does not eliminate all delivery discrepancies. It changes the nature of them.
Counting methodology differences. A buyer's impression counter and a publisher's impression counter use different counting logic. A buyer counts impressions at bid request; a publisher counts impressions at ad serving. These will never produce identical numbers. The DealSheet does not resolve this, but it does provide a shared reference for what level of discrepancy is within acceptable tolerance.
Out-of-scope delivery. If the campaign serves impressions outside the agreed inventory scope, the DealSheet makes this visible. The buyer can check whether the impressions their system logged were within the inventory parameters the DealSheet specifies. An out-of-scope impression is a discrepancy against the DealSheet, not against a disputed interpretation of what was verbally agreed.
Threshold triggers. If the delivery commitment in the DealSheet was not met, the shortfall is documented against the shared reference, and the remedy, whether a credit, a make-good, or a rate adjustment, is calculated against the agreed terms rather than negotiated from opposing positions.
What both parties need to reconcile effectively
For DealSheet-based reconciliation to work, both parties need to be able to access the deal record independently. The marketplace that holds the DealSheet must provide retrieval access to both the buyer and the publisher, not just to one party with the other relying on a shared export.
Both parties also need delivery data that can be mapped against the DealSheet fields. A buyer's impression log that does not record the inventory context in which each impression was served cannot be used to verify whether delivery was within the agreed inventory scope. This is a data infrastructure requirement that some buyers will need to address before DealSheet reconciliation can be used to its full potential.
The practical benefit for most buyers in the near term is simpler: a shared deal record that both parties agree on before the campaign runs eliminates the most common source of post-campaign disputes. Whether or not the delivery data is detailed enough for full scope verification, having an agreed CPM and agreed delivery commitment in a shared document reduces reconciliation time and reduces disputes at the term level. The scope verification layer can be added as data infrastructure matures.