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If your demand partner is being called directly by your ad server, you will need to ensure the custom “context” key and all values flow through from your initial ad request to your demand partners
This is done using macros inserted into your demand partner ad tags that reference the “context” values passed to your ad server
Your demand partner should specify which key in their ad request needs to be populated with the “context” values, as this will be different from partner to partner
In GAM, “cust_params” are pulled out and passed to demand partners using the Pattern Match Macro
Google documentation on the Pattern Match Macro can be found on this page: https://support.google.com/admanager/answer/2376981?hl=en
Telaria uses the key “c4” to pass context values in their requests. Here is an example of a Telaria tag populated with GAM’s Pattern Match Macro that will pull out the “context” values sent in the cust_params section of the initial ad request:
https://5tmwh-tr5hk.ads.tremorhub.com/ad/tag?adCode=5tmwh-tr5hk&playerWidth=%%WIDTH%%&playerHeight=%%HEIGHT%%&playerPosition=preroll&videoTitle=%%VIDEO_TITLE%%&videoId=%%VIDEO_ID%%&c4=%%PATTERN:context%%&srcPageUrl=%%REFERRER_URL_ESC%%…
If not using GAM and Telaria, please consult your ad server on which macros to use to pass the “context” values, and consult your demand partner on which key to populate those values into
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The “context” key-value pair can be used with the following SSPs:
Beachfront
Rubicon
Telaria
SpotX
Verizon
Adx
Xandr
Rhythm One
Passing the Values in the “iris_id” Custom Key Value Pair from the Ad Server to Your Supply-Side Partners
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