A sponsorship is a high-priority line item that you sell for a percentage of requests. This type of advertising is sometimes called "share-of-voice" because the advertiser gets a certain share of the page views on your site. Sponsorships are generally time-based ads.
Sponsorships are sold on the basis of cost per thousand impressions (CPM), cost per click (CPC), or cost per day (CPD). They can use all of the available targeting criteria; when you use targeting, the percentage basis becomes the percentage of matching impressions.
How sponsorships work
Sponsorship line items are goal-based. You set a percentage goal for each line item, which is used to determine the percentage of matching requests for which each sponsorship will be served.
Sponsorships are served ahead of other line items of the same priority, up to the goal you set. If you set the goal to 100%, and no other sponsorship targets the same inventory and criteria, then the sponsorship will be served exclusively. If you set a percentage less than 100%, line items of equal and lower priority can be served along with the sponsorship.
When multiple sponsorships targeting the same or overlapping inventory and criteria have goals that add up to more than 100%, things get complicated. Delivery patterns become harder to predict. It's best to avoid contending sponsorships with overbooked percentages.
When sponsorships contend for impressions beyond 100%, delivery is based on the ratio of each line item's percentage to the total booked percentage:
For example, you've booked three sponsorship line items for your homepage, with no additional targeting. Using the formula above, you get the following results:
|Sponsorship||Booked percentage||Delivered percentage|
Delivery of competing sponsorship line items is not affected by price.