Considering our definition of MS, MS on Patient.link seems appropriate. We will keep MS here, and also better give guidance to app developers, for example: basic expectations follow the link understand direction understand "active flag" understand link.type inactive patients may have relevant information Additionally, we will add additional content to https://build.fhir.org/ig/HL7/fhir-ipa/branches/2022Jan-recon/conformance.html , explaining to specification authors that they may have different MS on the same fhir data element than IPA for servers, and remain "compatible" as long as they clearly identify these differences.