Dupe
Dupe is a player term short for duplicate, which is an explicitly illegal and bannable offense in Ultima Online. Dupe can refer to both the cheating process of duplicating an item as well as the item created by the duping process. Duper refers to the person perfoming the act.
In any case, dupers are typically dealt with harshly with their game account and all belongings deleted as well as any accounts using the same credit card or personal information. Other players knowingly in possession of duped items or sharing knowledge of duping are typically also dealt with in a similar manner.
Quite simply, duping in Ultima Online is a serious offense of the highest magnitude and anyone caught associated with it will most likely be removed from the game with virtually no prospect of reprieve. Accordingly, there is little sympathy among the player community for dupers as they contribute to the detriment of the game as a whole.