If he walks in and out of the office, but passes to desks, and at these desks claims are processed for payment. Could this be a possible HIPPA violation?

Are medical details been divulged ?

No. No different than mail delivery.

It's the responsibility of the medical offices to keep papers from view of ANY person who is not supposed to see them. No one knows what might be seen by someone who knows the person and info showing. If you work there and you know that UPS or any other people can see what is on desks, then report it as a suggestion to improve security.

Asking a hypothetical is difficult to answer. Are you someone whose information was read off of a claim by a UPS person, or what?

HIPAA protects patients from from having their medical information released by a medical provider to an unauthorized third party. As joy said it is up to the third party to protect info from prying eyes. If info is left in plain sight so anyone walking around can see it, and unauthorized people are allowed to walk around, then the medical office could be cited for violations.

Why are you asking? Why is a delivery person allowed to walk around the offices? Isn't mail and other deliveries handled at the front desk or in a mail room?