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Authentication provides who the requesting user is, while Authorization provides what the requesting user has access to. Authorization is required in order to use any of the external APIs. The authorization endpoint provides the API user with the partners and advertisers they have access to within ui.marketing. The authorized partners will have an authorizationId associated with it that can be retrieved from the API response. From there, permitted advertisers can be retrieved. This authorizationId will be needed for all other external APIs.
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