Techniques for making and using recoverable marks for films. The recoverable mark consists of a portion of a film to which a watermark that is imperceptible to viewers of the film has been applied and an original mark that is applied to the portion of the film with the watermark. Application of the original mark to the portion modifies the watermark, and consequently, if the original mark is altered, the modifications to the watermark preserve the original mark. In one application of the technique, the watermark is applied to a digital master of the film, a master analog copy is made from the digital master, and a unique original mark is applied to each of the copies made from the master analog copy.