The term ashcan, coined during the Golden Age referred to the practice of creating a physical comic book for purposes of registering the trademark for titles and logos to the U.S. Patent and Trademark Office. It is rare for early ashcans to have survived. Ashcans are now used as a marketing device by publishers and are the equivalent of a preview. Modern ashcans will be included in this list if their resale value exceeds the amount of their initial selling cost.