主权项 |
1. A method for a server computer system comprising:
receiving, from a user agent, a call requesting a creative for a first slot of a plurality of slots, wherein the first slot is part of a template associated with a content item, the template to define a layout of the plurality of slots; determining, by a processing device, whether an ownership period associated with the first slot has expired; when the ownership period associated with the first slot has not expired, selecting, in view of rules and constraints associated with the first slot, a creative from a campaign associated with an advertiser that owns the first slot for the ownership period; and serving, to the user agent, the selected creative for the first slot. |