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Once the results have been produced, the AttributeFilterConfiguration is applied to the results. This is a reversal of the usual filtering process of outbound data and operates with the proxying IdP itself as the "requester" and the proxied IdP as the "issuer", applying the Requester- and Issuer-based rules, respectively. It is also often desirable to apply "scope filtering" based on metadata when defining acceptance rules for scoped attributes.
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