I have an authentic RFC number (from a car purchase a couple of years ago? Don't remember.) This number was confirmed when I recently went to the SAT.gob site (I took a screenshot—not proof, I know, but it is in the system). But…I don’t recall ever getting any card or document proving it, like I have for my CURP. Is there some card or document available proving your RFC? I wonder, will a bank, CFE, and other entities just input the number I scribble on a scrap of paper, and find out for themselves if it is valid? Anyone encounter this?