Abstract: Systems, methods, and computer-readable storage media that may be used to populate a content interface having several positions are provided. One method includes determining a first set of eligible content bids by comparing a performance characteristic of each content bid with a first threshold value. The method further includes conducting a first auction process on the first set of one or more eligible content bids to determine one or more first content items to be displayed in at least one position of a content interface. The method further includes determining a second set of eligible content bids by comparing a performance characteristic of each content bid with a second threshold value. The method further includes conducting a second auction process on the second set of one or more eligible content bids to determine content items to be displayed in at least one other position of the content interface.

Abstract: Systems, methods, and computer-readable storage media that may be used to populate a content interface having several positions are provided. One method includes conducting at least one first auction process to select a first set of one or more winning content bids based in part on a first eligibility constraint. The first eligibility constraint includes a limitation on the number of winning bids that share a particular characteristic. The method further includes, when the number of winning content bids is less than a number of positions within the content interface, conducting at least one second auction process to select a second set of one or more winning content bids by either disabling the first eligibility constraint or applying a second eligibility constraint. The second eligibility constraint permits a larger number of winning content bids to share the particular characteristic than are permitted under the first eligibility constraint.