It would be missing a prominent blue holographic stripe running through the paper.

Do you know how to detect a bleached bill that has been re-printed as a $100 ?

Your pen says it is legit.

P2P_bitcoin

As the buyer of cash?  (i.e., paying with bitcoin? ) 

bitcoin

P2P trading etiquette

Great write up.

Two additional thought:

- As the buyer you may want to buy a counterfeit testing pen.  They are relatively cheap and great EDC tool in this situation.

- If onchain transaction, may want to confirm ahead of time number of confirmed blocks needed for confirmation.
