Shostack + Friends Blog Archive


Return Addresses

Canada Post has apparently told the world that they’ll only deliver mail with a return address. This is clearly silly, phone books are full of valid return addresses for your city. Over at StupidSecurity, nrh asks:

Part of the reason I delayed was that I was trying to find out if this was even legal. A talk by Rob Pike at USENIX many years ago described the US as belonging to some sort of universal postal agreement that required it to make a best attempt to deliver mail it accepted no matter what the addressing format.

I’m afraid I haven’t yet found out if this agreement exists, or if the new Canadian policy is consistent with it, and if Canada belongs to this agreement. Anyone know?

I’m confident that the “Universal Postal Union” is the one with the treaties. They do encourage using the form that the recipient’s post office wants, but you can probably find the treaties on there.