As much as I enjoy watching a bunch of grown-ass pharmacists bickering over this, I'm bored at work so decided to look into this myself.
So after looking at that letter from the DEA written in 2017 that
@CetiAlphaFive posted. Here's my unbiased take, for what its worth.
If I as the physician send in a controlled prescription electronically, you can transfer it to another pharmacy provided it is unfilled. If you receive the prescription via verbal order or paper (whether faxed or brought in by hand from the patient), you cannot transfer that to another pharmacy unfilled. If you receive the prescription via verbal order or paper, after the initial fill you can transfer any refills to another pharmacy.
I have no idea who this makes right and who this makes wrong, but that letter seems pretty straightforward. Its recent. And its directly from the DEA.