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How do I configure my IdP to release the absolute minimum attributes required?
In that caseIf your software supports it, you should can release a dynamic subset of the R&S attribute bundle based on the list of requested attributes in SP metadata.
How do I get my IdP on the official list of IdPs that support R&S?
Once you've configured your IdP to release the R&S attribute bundle, you declare your IdP's ability to support R&S by submitting a short form. Normally such an IdP would be added to the list within one business day.