What is Open Bidding?
Open Bidding enables ad sources to compete in a real-time auction to fill your ad requests. This helps ensure you’re getting the highest revenue for your impressions.
Unlike traditional mediation, which relies on user-provided eCPM or historical data to prioritize networks and call them one at a time, Open Bidding calls all participating ad sources simultaneously. The ad sources bid on each impression in real time. This allows them to compete equally in a single, unified auction.
For any given impression, the ad source that serves the ad is the highest paying advertiser.
How does Open Bidding work?
Open Bidding works seamlessly with existing or new mediation groups. Each Open Bidding ad source competes to fill ad requests along with the other ad sources, like waterfall ad sources, which do not participate in Open Bidding.
1. An ad unit generates an ad request
An ad unit in your app generates an ad request and sends it to AdMob along with targeting information, such as platform and ad format.
2. AdMob matches the ad request to one of your mediation groups
AdMob mediation compares the ad request to the targeting settings and priority of the mediation groups you've defined. It matches the ad request to the mediation group with the correct targeting settings and, if there is more than one, the highest priority.
3. AdMob initiates an Open Bidding auction
Once the ad request is matched to a mediation group, the Open Bidding ad sources in the group compete in an auction to fill the request.
The ad source that submitted the highest eCPM bid will then be placed in the mediation waterfall according to the eCPM value.
4. Mediation waterfall functions as usual and the ad request is filled
If an Open Bidding ad source is placed first in the mediation waterfall, it will serve the ad.
If the Open Bidding ad source is not the highest eCPM in the mediation waterfall, the waterfall ad sources will be called first.
Currently, Open Bidding ad sources do not support ad serving for the following:
- Child-directed apps or ad requests. Learn more.
- GDPR ad requests. Learn more.
- CCPA ad requests. Learn more.
- Ad requests in Russia and China.
Similarly, your Open Bidding ad sources must be included as an ad technology provider. To select ad technology providers in AdMob, click Blocking controls in the sidebar and click the EU user consent tab.
Example 1: Open Bidding mediation group
There are 4 Open Bidding ad sources in the mediation group. Each source submits a bid for an available ad unit. In this example, there are no waterfall ad sources in this mediation group. This means that the highest bidding ad source serves the ad.
Example 2: Open Bidding and waterfall ad sources in a mediation group
There are 4 Open Bidding ad sources in the mediation group. Each source submits a bid for an available ad unit.
Network B wins the Open Bidding auction with a $7 bid and is placed according to its eCPM value in the mediation waterfall. In this example, Network B’s bid is higher than other waterfall ad source bids. Therefore, Network B is placed first in the waterfall and gets to serve the ad. The waterfall ad sources are not even called.
In this example, Exchange B wins the Open Bidding auction with a $4 bid and is placed according to its eCPM value in the mediation waterfall. However, Network 1 has a higher eCPM value ($5) than the winning bid from Exchange B. Therefore, Exchange B is placed second in the waterfall.
From now on, the waterfall functions normally. Network 1 serves the ad if it has one. If not, Exchange B will serve the ad.
Example 4: Open Bidding with direct sold in a mediation group
In this example, Exchange A wins the Open Bidding auction with an $8 bid and is placed according to its eCPM value in the mediation waterfall. However, your direct sold campaign has a higher eCPM value than the winning bid from Exchange A. Therefore, Exchange A is placed second in the waterfall.
From now on, the waterfall functions normally. Your direct sold campaign serves the ad if there is one. If not, Exchange A will serve the ad.
Get started with Open Bidding
First, you’ll need to set up a partnership with an Open Bidding ad source. In many cases, this is as simple as creating an account on the ad source's home page. Learn more about the ad sources that support Open Bidding.
Next, add your Open Bidding ad sources to existing or new mediation groups.
To use Open Bidding, ensure that you’ve integrated Open Bidding mediation into your app. Also note that some ad sources may have additional SDK requirements.