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Playbooks · Inventory pricing

Choose between a PMP deal and the open exchange

This job produces a go/no-go allocation decision between a PMP deal and the open exchange for a specific budget line. It feeds the trafficking step where the buyer sets up the DSP line item with either a Deal ID or open auction targeting.

What you need first

  • Confirmed budget and flight dates from the media plan
  • PMP deal terms (floor CPM, Deal ID, inventory whitelist) from the publisher or SSP deal sheet
  • Open exchange trailing win-rate CPM and available volume for the same inventory pool from DSP historical reporting (last 30-90 days)
  • Viewability and in-target rate by path from the verification vendor report (IAS, DoubleVerify, or equivalent)
  • Minimum scale requirement (impressions or reach) from the media plan

The procedure

  1. Pull the PMP floor CPM, Deal ID, and inventory scope from the deal sheet and confirm it matches the plan's placement list.
  2. Pull the open exchange's trailing win-rate CPM and available volume for the same inventory pool from DSP reporting.
  3. Pull viewability and in-target rates for each path from the verification vendor report.
  4. Calculate effective CPM for each path: headline CPM divided by (viewability rate times in-target rate).
  5. Calculate deliverable effective impression volume for each path at the confirmed budget.
  6. Compare effective CPM and effective volume against the plan's minimum scale requirement to pick full PMP, full open exchange, or a split.
  7. Set the Deal ID in the DSP line item, or set exchange and inventory targeting parameters for open exchange, and confirm the line is live at the chosen split.

Worked through with numbers

Budget: EUR 40,000 for a 30-day display flight in Poland. PMP deal sheet: floor CPM EUR 7.00, viewability 82%, in-target 90%. Open exchange trailing 60-day report for the same inventory pool: average winning CPM EUR 4.20, viewability 58%, in-target 75%. Effective CPM = CPM / (viewability x in-target). PMP: 7.00 / (0.82 x 0.90) = 7.00 / 0.738 = EUR 9.49. Open exchange: 4.20 / (0.58 x 0.75) = 4.20 / 0.435 = EUR 9.66. Raw impressions at budget: PMP 40,000 / 7.00 x 1000 = 5,714,286; open exchange 40,000 / 4.20 x 1000 = 9,523,810. Effective (viewable, in-target) impressions: PMP 5,714,286 x 0.738 = 4,217,143; open exchange 9,523,810 x 0.435 = 4,142,857. PMP wins on both effective CPM (EUR 9.49 vs EUR 9.66) and effective volume (4.22M vs 4.14M) despite the higher headline rate, so commit the full budget to the PMP deal.

Where it goes wrong

  • Compare effective CPM, not headline CPM; headline CPM alone understates the open exchange's true cost once viewability and in-target rate are applied.
  • Treat a Deal ID as a delivery guarantee only when a floor and priority have actually been negotiated with the publisher; an unpriced or low-priority deal ID can go unfilled and starve the line.
  • Check the open exchange's historical win rate for the specific inventory pool before assuming it can absorb the full budget; thin pools cap deliverable volume well below plan.
  • Revisit the split at the midpoint of the flight; effective CPM drifts as competition for the deal changes, so a single upfront decision can leave the back half of the budget on the worse path.

How to know it is right

Recompute effective CPM from the same viewability and in-target rates in the vendor report and confirm both paths' numbers match the worked comparison within rounding before handing off to trafficking.

Terms used

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