Partner Data represents any signals that a partner is able to pass to ID5 to help recognize the user.  Browsers are taking increasing steps to obfuscate signals to third parties, therefore to maximize the addressability of your audience, ID5 requires publishers and advertisers to send IP address and user agent into the pd string and recommends the provision of hashed emails, mobile ad ids and any other signals for consented users when available.  If there are any signals you feel might help reconcile your users across your properties, please discuss this with your ID5 representative and we will advise you of how to pass them through. If you do not want to pass signals through a client side integration, please reach out and we can discuss server side options. 

Signals passed in the ID5 ID request, are used to inform ID5 ID generation and linking users across domains. “Hard signals” such as hashed email addresses take priority for cross-domain linkage purposes. ID5 performs a real-time look-up for the value provided and returns the ID5 ID that was already associated with that value. If the value doesn’t exist in the ID5 database, a new ID5 ID is created and provided in the response. 

Publisher provided signals such as IP address and user agent may be used in ID5’s probabilistic algorithm when ID5 deems that they may be more accurate than those that ID5 can source directly from the http request. ID5 requires sha256 hashing & URL-safe base64 encoding to ensure that personally-identifiable information isn’t transmitted in the ID5 ID call.