Writing on the back on the envelope

[JMRevolution]

Hey guys,

I'm curious, is writing on the back of the envelope to denote where the letter comes from compulsory?

I wonder if it raises eyebrows if its got someones name on the back and it mentions of someone with a big name that'll make em raise an eyebrow....so i was wondering if its compulsory to write it?

Cheers!

[admin]

Hi

https://pe.usps.com/text/dmm100/addressing-mail.htm

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