Short answer
There are four ways to buy programmatically. Open auction: any buyer bids on any impression. Private marketplace (PMP): an invitation-only auction run by a publisher. Preferred deal: a fixed price for unreserved impressions, offered to you first. Programmatic guaranteed: a reserved volume at a fixed price, bought automatically. B2B buyers usually get the best value from PMPs and preferred deals with publishers their buyers read, plus a small open-auction line for reach.
The four types
| Type (IAB name) | Price | Volume | Who can buy |
|---|---|---|---|
| Open auction | Auction | Not guaranteed | Any buyer |
| Private marketplace (invitation-only auction) | Auction, usually with a floor | Not guaranteed | Invited buyers |
| Preferred deal (unreserved fixed rate) | Fixed | Not guaranteed; you see it first | One buyer |
| Programmatic guaranteed (automated guaranteed) | Fixed | Reserved | One buyer |
In the IAB's words, automated guaranteed deals "are the most like traditional direct ad buys but are now handled automatically"; in an invitation-only auction "publishers offer ad impressions to a select group of preferred advertisers"; in the open auction they offer impressions "to any and all buyers".
Which ones fit B2B
| Goal | Best fit | Why |
|---|---|---|
| Reach the buying committee on trade and business media | PMP or preferred deal | Known sites, better viewability, controllable context |
| A launch or event takeover | Programmatic guaranteed | Reserved volume on specific pages and dates |
| Account-list reach at scale | Open auction with inclusion lists | Enough inventory to find matched accounts |
| Retargeting | Open auction and PMPs | Follows the visitor wherever they read |
Why it matters in B2B
The ANA's 2023 study of programmatic campaigns found the average campaign appeared on about 44,000 websites, with made-for-advertising sites taking 21% of impressions. B2B buyers are a small share of any site's audience, so buying where they read, through deals, usually costs more per thousand and less per engaged account.
Setting up a deal
- Shortlist publishers your buyers read; check their ads.txt lists your DSP's sellers. How to check.
- Agree format, price or floor, dates and targeting; receive a deal ID.
- Add the deal ID to a separate line item, so you can report it alone.
- Check delivery within 24 hours; a deal that doesn't bid is the most common failure.
- Compare deals on vCPM and cost per engaged account, using the max CPM calculator for your ceiling.
Questions
What is a PMP?
A private marketplace: an invitation-only auction where a publisher offers its inventory to selected buyers, usually with a floor price and a deal ID.
What is the difference between a preferred deal and programmatic guaranteed?
A preferred deal gives you a first look at a fixed price without guaranteed volume. Programmatic guaranteed reserves a set number of impressions at a fixed price.
Is open auction bad for B2B?
Not by itself, but it's where low-quality and made-for-advertising inventory concentrates. Use it with inclusion lists and viewability conditions.
How do I get a deal ID?
Agree terms with the publisher or its SSP, receive a deal ID, and add it to a line item in your DSP. Check it's delivering within a day.
Facts checked against the sources below on 19 October 2026. Ad platforms change quickly: if something here no longer matches what you see, tell us and we will update it.
