A bidder can purchase inventory for multiple buyers in a single bid response. For example, a demand-side platform (DSP) might use its bidding application to purchase inventory for several marketers or agencies who are buyers. This guide explains how to code your bidder to process a single request sent on behalf of multiple buyers.
Background
In some scenarios, an ad network or agency trading desk may choose to work with one or more DSPs. There are two options available for buyers who work through a DSP:
- The DSP purchases inventory for marketers or agencies that are not buyers. In this case, the DSP receives one bid request and responds with one bid. Google bills the DSP directly.
- The DSP purchases inventory for marketers or agencies that are buyers. The DSP receives one bid request including multiple billing IDs associated with eligible buyers, and can place distinct bids for each buyer they intend to bid on behalf of. In this model, Google bills the buyer, not the DSP. The rest of this guide focuses on this scenario.
Setup and pretargeting
Google will send a bid request containing one or more billing IDs associated
with buyers and pretargeting configurations that targeted the impression.
These can be found with the BidRequest.imp.ext.billing_id
field.
When responding to a BidRequest
that contains billing IDs from
multiple buyers, BidResponse.seatbid.bid.ext.billing_id
is
required so that Google knows which account to associate with the bid. Any
response that does not set the field is filtered. The field remains optional
for any BidRequest
that only includes a single billing ID.
Pretargeting example
A bidder bids on behalf of two buyers, one having a billing ID of 123, and the other with billing ID 124. The bidder configures one pretargeting configuration with billing ID 213 to target the English language, and another with billing ID 231 to target personal computers. The following describes the billing IDs that appear in bid requests for different kinds of impressions.
Impression description | Billing IDs in bid request |
---|---|
Japanese language content on a personal computer. | 123, 124, 231 |
English language content on a mobile phone. | 123, 124, 213 |
English language content on a personal computer. | 123, 124, 213, 231 |
Example BidRequests
Below are examples of a BidRequest
. You'll note that there are multiple billing IDs
in these requests because the requests are applicable to multiple accounts.