PMP advertising: how a site list becomes a curated deal
The short answer
A private marketplace (PMP) deal is an invitation-only arrangement between a seller and chosen buyers, set up on an exchange and identified by a deal ID. Its terms include floor price, currency and allowed buyer seats. A curated deal applies the same mechanics to a package of inventory, which can come from many publishers, assembled to a buyer's criteria.
Key takeaways
- A deal ID is a label the exchange attaches to eligible impressions; the buyer's platform bids on that ID under the agreed terms.
- Private auctions, fixed price deals and programmatic guaranteed deals differ in price, priority and whether the buyer must bid.
- A curated deal is only as good as the site list behind it, so the list is checked before the deal is built.
- Exporting an approved list does not create a deal: the seller or curator sets it up and the buyer activates it.
- Before launch, confirm the deal ID, seats, floor currency, geography, formats and the list version on both sides.
What is a private marketplace deal in programmatic buying?
Definition
- Private marketplace (PMP)
- An invitation-only way to buy programmatic inventory, in which a seller makes specific impressions available to named buyers under agreed terms, identified by a deal ID on the exchange.
The OpenRTB 2.6 specification, the IAB Tech Lab protocol for real-time bidding, describes the Pmp object as the private marketplace container for direct deals between buyers and sellers that may pertain to an impression. When a bid request includes a Pmp object with one or more Deal objects, the impression is available under the terms of those deals. A bid made under a deal returns the deal's ID, so both sides can report on it.
The ANA's Q4 2025 Programmatic Transparency Benchmark (opens in a new tab), released in February 2026 and the latest public release to report the share, found that private marketplaces accounted for over 92 percent of median spend across environments and 100 percent of CTV transactions, and that open marketplace buying "became more selective, governed by inclusion lists and performance filters." The figure describes the benchmark's participants, not every advertiser in the United States or Canada.
What deal types do buyers use, and how do they differ?
Deal type names vary by platform, but the terms behind them map to a few fields in the OpenRTB 2.6 specification (opens in a new tab). Knowing the field tells a buyer what the deal really commits each side to.
| Deal type | How it works | OpenRTB signal | Buyer must bid? |
|---|---|---|---|
| Private auction | Invited buyers bid against each other above a floor | private_auction set to 1 restricts bids to the listed deals; bidfloor sets the minimum | No |
| Fixed price or preferred deal | One buyer, or a few, can buy at an agreed price before the open auction | at set to 3 means bidfloor is the agreed deal price | No |
| Programmatic guaranteed | Price and volume are agreed in advance and the buyer commits to take the impressions | guar set to 1 marks a guaranteed deal that the bidder must bid on | Yes |
| Deal alongside open auction | The deal competes with open bids on the same impression | private_auction set to 0 accepts all bids | No |
What is a curated deal, and how is it different from a publisher PMP?
A publisher PMP packages one publisher's inventory. A curated deal packages inventory from many publishers, selected to a set of criteria such as topic, quality checks, geography or format, under one deal ID. The curator may be the exchange, the agency, a third party or the publisher group itself. For the buyer the mechanics are the same: one deal ID to target, with terms set on the exchange.
Because more parties now package deals, IAB Tech Lab has worked on describing them consistently. Its Deals API (opens in a new tab) version 1.0, finalized on February 6, 2026 after public comment closed on January 31, standardizes how deal terms move from the system that created a deal, such as an SSP, to the receiving system, such as a DSP. Tech Lab's 2026 OpenRTB roadmap article (opens in a new tab) describes a Curation object showing who sold the deal, who packaged it and who curated it. A final specification is not proof that a given platform has implemented it, so ask each partner.
What is a deal ID, and what travels with it?
The deal ID is a string the exchange creates, required and unique for each deal. The buyer enters it in the buying platform, in a deal or inventory library, and targets it in a line item or campaign. The ID itself carries no terms; the terms sit with the exchange and arrive in each bid request in the Deal object.
| Field | What it controls | What to confirm |
|---|---|---|
| id | The unique identifier for the deal | The ID in the buying platform matches the one the seller sent |
| bidfloor and bidfloorcur | The minimum CPM and its currency, which defaults to USD if not set | Canadian buys priced in CAD state the currency explicitly |
| at | Optional auction type override; 3 means the floor is the agreed price | The price model matches the signed terms |
| wseat | Buyer seats allowed to bid; seat IDs are agreed in advance | Your seat ID on the exchange is on the list |
| wadomain | Advertiser domains allowed to bid | The brand's domain is listed, or the field is empty |
| guar | Whether the deal is guaranteed and must be bid on | Both sides agree on whether volume is committed |
How does a site list become a curated deal?
Steps from list to deal
- Approve the site list. Lock the version that the client signed off, with a reason for each site, so the deal can be traced back to it.
- Keep only sites the exchange can sell. Check each site's ads.txt and the exchange's sellers.json, as described in our supply path guide, and set aside sites the exchange does not sell.
- Write the deal sheet. State geography, languages, formats, list size, price model, currency, flight dates and the buyer seat ID.
- Hand the list to whoever builds the deal. Upload the domain file in the exchange's documented format, or send it to the seller or curator who sets up the deal.
- Receive and enter the deal ID. Add it to the buying platform and target it in a campaign or line item.
- Reconcile after launch. Pull the deal's served domain report and compare it with the approved list.
What should buyers confirm before activating a PMP or curated deal?
Pre-activation check for a private marketplace deal
- The deal ID in the buying platform matches the seller's confirmation character for character.
- Your buyer seat ID, and the brand's domain if the deal restricts advertisers, are allowed on the deal.
- The floor price, currency and price model match the agreed terms.
- The deal's domain list is the approved version, with the same site count.
- Geography and languages on the deal match the brief, including Canadian French where needed.
- The creative formats and sizes you will traffic are ones the deal's inventory supports.
- Campaign targeting in the buying platform does not narrow the deal so far that it cannot deliver.
- Someone is named to check delivery and the served domain report in the first days of the flight.
Why might a private marketplace deal not spend?
A deal that shows no delivery can be blocked by a mismatch between what the seller set up and what the buyer targets. Work through the causes in order, from the deal's terms to the campaign's own settings.
| Symptom | Likely cause | What to check |
|---|---|---|
| No bid requests with the deal ID | The deal is not active on the exchange, or the domain list holds few sellable sites | Deal status and dates with the seller; how many listed sites the exchange sells |
| Requests arrive but no bids | Seat not allowed, floor above the bid, or currency mismatch | wseat, bidfloor and bidfloorcur against the line item |
| Bids but no wins | Bids sit at the floor while other deals or buyers win the same impressions | Bid price and priority with the seller |
| Wins on very few sites | Campaign geography, format or frequency settings exclude a large part of the list | Overlap between campaign targeting and the deal's inventory |
How does PlacementGraph prepare a site list for a curated deal?
Fictional example
A curated deal for a Canadian cycling brand
A fictional Calgary bike maker, Vellicor Cycles, wants display and video beside commuting and city cycling content in Alberta and British Columbia, in English. The planner builds a site list from the brief, removes sites the chosen exchange does not sell, and gets the client's approval.
The trading desk sends the approved domain file and deal sheet to the exchange, which creates a deal priced in CAD with the desk's seat allowed. The desk enters the deal ID, checks the currency and seat, and reviews the served domain report after the first three days.
Guides in this hub
Every guide in the Curated deals and PMPs hub, each written to answer one question in full.
- How-toHow do you add a deal ID to a buying platform and confirm it bids?Steps to add a deal ID to a buying platform: what the hand-off must include, how to target it in a line item, how to confirm bid requests and how to store it.
- GuideAge restricted ad inventory: using private deals to keep ads in front of adultsHow alcohol, cannabis and gambling advertisers use private deals to limit inventory to adults, why no deal guarantees age, and what evidence to request.
- GlossaryAgency private marketplaces: how agency deals reach client campaignsWhat an agency private marketplace is, how agency deals reach client campaigns, who owns the terms, and what clients should ask about reporting and fees.
- GuideBrand suitable deals: what deal composition can enforce, and what still needs checkingHow deal composition enforces brand suitability with vetted sites, section scope and publisher exclusions, and which checks still need verifying after launch.
- GlossaryWhat is a buyer seat ID, and why does each deal need the right one?A buyer seat ID names the buying account an exchange lets bid on a deal. See how publishers use it, how to find yours and what breaks with the wrong seat.
- GuideCanadian PMP: running private deals in Canadian dollars and in FrenchHow private deals work for Canadian campaigns: CAD floors in the bid request, packaging French inventory, IAB Canada's 2025 buying data and publishers to ask.
- GuideContextual PMP: keeping a site list's context intact inside a private dealHow to turn a contextual site list into a private marketplace deal, keep the topic intact through setup, and check the deal ran on pages that match the brief.
- ExplainerCreative approval in PMP deals: who reviews the ad, and how rejections stall deliveryHow creative approval works in PMP deals: who reviews, how publisher blocks apply to private auctions, why creatives get rejected and how to plan review time.
- GuideCross exchange deals: running one site list on several exchangesRun one approved site list as deals on several exchanges: avoid bidding twice on one impression, keep the lists in sync, explain uneven delivery and report it.
- GlossaryWhat are curated audiences, and how do they reach a bid request?What IAB Tech Lab's Curated Audiences specification is, why Seller Defined Audiences was renamed, how its signals travel in OpenRTB, and what buyers should ask.
- GuideA curated deal example, from the brief to the first weekA fictional curated deal followed from brief to site list, deal sheet, seller setup, desk activation and first week checks, with who does each step and why.
- How-toCurated deal maintenance: keeping an approved site list currentHow to keep a curated deal's site list current after approval: removals, sellers that stop selling, approving additions, review dates and change notices.
- ChecklistWhat belongs on a curated deal sheet, and who fills it in?What a curated deal sheet should hold, who fills each part, how to show sellers per site and per exchange, how to flag unverified sellers and how to version it.
- ExplainerHow curation changes a deal's supply path, and how buyers trace itHow a curated deal changes the supply path, when a curator shows up in schain and sellers.json, whether curation shortens paths, and the logs that trace it.
- ChecklistCurator transparency questions to settle before a curated buyCurator transparency questions for curated deals: fields naming seller and curator, how to see the sites, what fees to disclose and where schain shows it.
- GuideDeal ad formats: how to write them so the deal can deliverHow to specify ad formats in a private marketplace deal: display sizes, native assets, rich media limits, and why a format mismatch quietly stops delivery.
- How-toDeal delivery reconciliation: proving a deal ran on its intended sitesHow to prove a curated or private deal delivered on its approved sites: which logs show domains, off list delivery, matching seller counts and the report.
- How-toHow to confirm each site in a deal can actually sellHow to confirm each site is sellable on the intended SSP, in the formats a deal needs, before it goes into a deal, and what to remove when inventory is missing.
- How-toDeal naming conventions: how to name deals so each ID stays traceableA deal naming convention that keeps PMP deal IDs traceable: which tokens to use, how to tie a name to a list version, safe renames and who owns the rules.
- GlossaryDeal priority in programmatic: why the ad server's order decides deliveryHow publisher ad servers rank guaranteed, preferred, private auction and open auction demand, what first look means and how to ask about a deal's priority.
- GuideDeal targeting settings: who sets each layer, and whereHow a deal's geography, devices and other targeting are set on the seller and buyer sides, how double targeting starves a deal, and how to record each layer.
- ChecklistDeal terms checklist: does the live deal match the agreement?A checklist for comparing agreed deal terms with the live setup before spend: deal ID, seat, price, auction type, formats, geography and dates, field by field.
- GlossaryDirect sold advertising: what it means for a buyerWhat direct sold advertising is, how direct buys work with a publisher, why premium space is sold direct, when buyers go direct and how it limits programmatic.
- GlossaryWhat is a floor price in programmatic, and how do deal floors work?What a floor price is in programmatic buying, how hard and soft floors work, how deal floors travel in OpenRTB and why a high floor can stop a deal spending.
- ExplainerWhat is the IAB Tech Lab Deals API, and what does it change for deal setup?What the IAB Tech Lab Deals API 1.0 standardizes, when it was finalized, which deal terms it moves from SSP to DSP, and the questions to ask partners about it.
- ExplainerWhy do impression counts differ between platforms, and how big is too big?Why publisher, SSP, DSP and ad server impression counts differ, what the standard terms say about a 10 percent gap, which count bills, and how to trace a gap.
- GlossaryWhat is an insertion order in advertising, and how does it relate to a deal?What an insertion order is in advertising, the fields it holds, who signs it, how it relates to programmatic deals and what standard terms say on underdelivery.
- GlossaryInventory packages in programmatic: what is inside the boxWhat publisher and exchange inventory packages are, who builds them, how to see the sites inside one, and what to ask before buying a package as a deal.
- GlossaryWhat is a makegood in advertising, and when does a publisher owe one?What a makegood is, the situations that trigger one under the standard terms, how makegoods work in programmatic guaranteed deals and how to record them.
- GlossaryWhat is the OpenRTB deal object, and how do buyers read it?A field by field guide to the OpenRTB 2.6 Pmp and Deal objects: private_auction, id, bidfloor, at, guar, wseat and wadomain, and what to check in deal logs.
- GuidePMP negotiation: which deal terms can a buyer shape before launch?A guide to PMP negotiation: which deal terms are open, what to ask the publisher, how reporting terms protect buyers, what to record and when to walk away.
- FrameworkPMP scale: how big does a deal need to be to spend its budget?A framework for PMP scale: why site count is a poor guide, how to estimate eligible impressions, when a deal is too small, combining deals and telling clients.
- ExplainerPreferred deals: how a fixed price and a first look work in programmaticA preferred deal gives one buyer a first look at a publisher's inventory at a fixed price, with no duty to buy. See how it runs, how to bid and when to use it.
- ExplainerProgrammatic curation: who packages the inventory, and what buyers should askWhat programmatic curation means in 2026, who curates a deal, how curators disclose data, fees and changing sites, and the questions a buyer should ask first.
- GlossaryWhat is programmatic direct, and which deals does it cover?Programmatic direct for buyers: which deal types it covers, how it differs from a direct insertion order and the open auction, and what both sides agree.
- ExplainerProgrammatic guaranteed: how reserved deals work and when planners use themProgrammatic guaranteed reserves inventory at a fixed price. Learn how deals are negotiated, what each side commits to, how billing works and when to use one.
- How-toHow to write a publisher proposal request that gets comparable answersHow to write a publisher proposal request for a programmatic deal: what to include, a reply window, scoring answers against the brief and the handoff after yes.
- GuideVideo PMP deals: what to specify before the first ad playsWhat changes in a video private marketplace deal: plcmt types, player size, sound, skip and length terms, completion tracking and checks before launch.
- ExplainerWhat is a deal ID, and how does it travel through a bid request?A deal ID labels one programmatic deal. See who creates it, where it sits in the bid request and response, how buyers traffic it and why a valid ID still fails.
- ExplainerWhy publishers use PMPs, and what they want from buyersThe publisher side of private marketplaces: price control, buyer choice, data, ad quality, priority, why deal requests get declined and how to ask better.
Frequently asked questions
Who creates the deal ID for a private marketplace?
The seller side creates it. A publisher, the exchange or a curator sets up the deal on the exchange, which generates the ID. The buyer receives the ID and enters it in the buying platform. A buyer can request a deal and propose terms, and the ID then comes from the system that sells the inventory.
Can one deal ID cover sites from many publishers?
Yes. That is how a curated deal works. The exchange or curator groups inventory from many publishers under one deal ID, using a domain list or other criteria. The buyer should ask for the domain list behind the deal and check it like any other inclusion list.
Is a PMP the same as programmatic guaranteed?
No. Programmatic guaranteed commits the buyer to take an agreed volume at an agreed price, and in OpenRTB the guar field marks it. A PMP deal without the guar flag is non-guaranteed: the buyer may bid, and the seller makes impressions available, but neither side commits to a volume.
What happens to a curated deal when a listed site stops selling through the exchange?
The deal stops receiving bid requests from that domain, and the buying platform may not flag the change. The site keeps its place in the domain list until someone removes it. Compare the deal's served domain report with the approved list after each flight, and replace sites that no longer appear in the exchange's sellers.json.
Sources
- OpenRTB 2.6 specification (opens in a new tab)IAB Tech Lab, OpenRTB repository
- Essential OpenRTB updates you can't ignore for your 2026 roadmap (opens in a new tab)IAB Tech Lab
- Curated Audiences (opens in a new tab)IAB Tech Lab
- ANA Q4 2025 Programmatic Transparency Benchmark Shows Media Quality Is Now Driving Measurable Performance Outcomes (opens in a new tab)ANA, February 25, 2026
- Deals API Specification (opens in a new tab)IAB Tech Lab, February 6, 2026
- sellers.json (opens in a new tab)IAB Tech Lab
Researched and written by PlacementGraph Research. Read how we research, source and update these pages. Corrections: diana@placementgraph.com.