A media buyer is participating in an auction where the highest bidder wins but pays exactly the price they bid. What type of auction is this?

In a first-price auction , the winning buyer pays the exact amount submitted in the winning bid. Google’s Display & Video 360 documentation states that non-guaranteed auctions can be first- or second-price, and that inventory goes to the highest bid above the minimum CPM. That payment rule is what distinguishes this model from a second-price auction , where the winner does not pay its full submitted bid. The defining mechanic here is that the clearing price equals the winner’s own bid. Google Help