Private Marketplaces (PMPs) in Real-Time Bidding (RTB) are customized, invitation-only RTB marketplaces where premium publishers make their inventory and audiences available to a select group of buyers. Unlike the open exchange, at auction the buyer knows which site/s the ad impressions will run on.
Here’s how it works:
A negotiation takes place between the buyer and seller to create and agree on a private deal.
During this process, a Deal ID is provided by the publisher and given to the buyer – and it can be used to set up their PMP in a Demand Side Platform (DSP).
Deal IDs act as a key to the private marketplace.
When a deal ID is negotiated, both parties are agreeing on two things: Approved access and a set of buying parameters like floor price and inventory type.
While private marketplace transactions are still subject to an auction, the competition is limited to buyers who have been invited to partake in the auction.
PMPs are home to exclusive inventory that is not available on the public market and usually targets a high-value audience.
Using a PMP is a strategic decision that can offer several benefits such as ensuring that ads are running at all times, achieving specific packages from a publisher, or when the advertiser is blocked in the open marketplace (like pharma or gambling).