You are mistaken about this. Many IOP's send their shipment via Registered mail (interpharm, to name one of them). Express mail that originates outside the US becomes registered mail once it enters the US. The official rule may be that only the recipient may sign for it, but the PO ALWAYS releases registered mail as long as you produce the peach-colored slip they leave for you. On many occasions, i've picked up regeistered mail without the slip.