The information being shared is not information that is considered 'sensitive' in the context where it's being shared.  The 'new' payer is already sharing demographic information and the demographics provided by the 'old' payer has to be well aligned or there wouldn't be a match.  In Coverage, the new payer already knows the old payer had coverage - or they wouldn't be trying to perform a match in the first place.  The member id and coverage id being shared would not be 'sensitive' and any use of them in interactions with the old payer would be governed by the old payer.  E.g. if the new payer performs a search using the member id, the old payer would determine what information is shared. The patient or their representative, by definition, has to be aware that the match is happening because that's the only way the new payer could have the information necessary to initiate the match.