Private Marketplace, abbreviated as PMP, is an advanced model in programmatic advertising where a publisher offers a select number of advertisers access to their ad slots through an exclusive and private auction environment. This allows advertisers to purchase ad space on a specific website or group of websites with greater control and exclusivity compared to the open real-time bidding (RTB).

PMP enables publishers to create a customized auction environment where they can handpick and limit which advertisers have access to their ad slots. This is particularly useful for protecting brand integrity and ensuring that ads are displayed in a quality and relevant environment.

For advertisers, PMP offers a chance to reach an engaged audience on high quality websites and apps, with more visibility into where their ads appear. It also provides the opportunity to negotiate prices and contracts directly with the publisher.

The PMP model combines the benefits of real-time bidding with exclusivity and control. It provides a balance between automated ad trading and quality control, which is particularly valuable for both publishers and advertisers who want a more customized and controlled advertising experience.