NPN refers to the term NO PURCHASE NECESSARY.
Card companies will include information on the backs of their card packs telling what odds you have at getting insert cards. You can also enter their NPN drawing by following the rules on the back of the pack and have a chance of getting those same cards at the same odds while supplies last. It usually involves sending a 3X5 note card in a number 10 envelope to the address they have listed. They will tell you what info you need to have on the card, the number of times you can enter and how long they will take entries for their drawing. Not everyone who mails will get a card back, but I personally have gotten autographs and game used cards for free this way in the past. Please feel free to use the info on this site to get entered and also please enter the info from the back of your packs in this forum to share with others. Thanks for your help and we would love to hear when you are sent an NPN winning envelope!