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The tracking domain is the domain via which ad impressions, clicks and conversions related to your advertiser are being tracked. You will need to register a tracking domain when you want to offer an advertiser first party tracking. First party tracking enables you to track your advertiser’s conversions and other conversions via the advertiser’s own domain. To find out why this is highly beneficial for both your advertiser and the partners on your platform, please read this First-party Tracking Setup article.
Please note, first party tracking should only be implemented when you are planning a long term implementation of your advertiser on your platform. In case you are only starting a brief campaign for an advertiser, you might want to use a generic tracking domain.
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