Nemo dat

Abbreviation for the Latin maxim “Nemo dat quod non habet,” literally meaning “one cannot give what one does not have.” What it refers to is the idea that theft cannot create good title, i.e., that a seller of stolen goods cannot convey ownership to the buyer. In intellectual property it means that even a purchaser of infringing goods who was unaware of the infringement does not have good title and may be obliged to Deliver Up the infringing items.