The CDEX Patient Demographic Profile is defined to capture the beneficiary's demographic information (member ID, name, DoB ) as contained resource in the Task resource.  The primary use case is when a Payer is requesting attachments from a Provider:

This Profile is defined to be [contained](http://hl7.org/fhir/R4/references.html) within the CDex Task Attachment Request Profile or CDex Task Data Request Profile. It is referenced when additional patient demographic data is communicated for a clinical data request (for example an attachment request by a payer to a provider). It constrains the following elements to be mandatory (min=1):
 

• A default resource ID of "patient"
• A member ID identifier slice
• A patient name

and the following element to be must support (min=0):

• A patient account number identifier slice
• A date of birth

 
This profile is not conformant with US Core Patient because gender is not mandatory. Patient gender is typically not communicated when requesting attachments using HIPAA compliant X12n 277 and 278 messaging.  In order to be able provide a FHIR alternative to these transactions.  We are requesting a variance from US Core for this narrow use case of contained Patient Resource for communicating defined patient demographic data.