An advertiser participates in a private auction. What happens if their bid isn't the highest?

In a private auction, while the inventory is restricted to a select group of invited advertisers, the fundamental auction mechanics still prioritize the highest bidder, meaning all impressions go to the advertiser with the highest bid. Unlike a Preferred Deal or Programmatic Guaranteed agreement where a specific buyer has a "first look" or a reserved volume at a fixed price, a private auction remains a competitive environment where multiple participants vie for the same impressions. If your bid is surpassed by another invited member, you will not clear any impressions for that specific request, as the publisher’s goal in this setup is to maintain a floor price while allowing competition among a curated group to drive the highest possible yield.