Someone I know just got a big mailing retuned. They didn't buy them here, but the same stock.
My assumption is that they are printed in China...
Even when using a real stamp from the post office which you know for sure is 100% a legit stamp, your never supposed to mail a boat load of invitations or letters in one mailbox, your supposed to break it up amongst a few mailboxes, whenever the USPS sees a lot of envelopes or letters they tend to chuck half of them thinking that they're fakes.
And in regards to the stamps they seem authentic or at least they been doing the job for me when putting a stamp of the right hand corner and depositing it in the mailbox.
When you "ASSuME" you make a "***" out of "U" and "ME"
Innocent until proven guilty.. 😋