When the MSR is signed by an Acceptable Medical Source (AMS) is there any HIPAA concern if the MSR contains information from other treating providers?

An MSR that has been written based on properly released records can be shared with the primary AMS.  At the point of obtaining the signature, it is primarily a privacy issue, not HIPAA. However, it would be a best practice to have a release signed by the applicant permitting the case worker to communicate with the AMS.