FIELD: preparation of securities bearing protection flag in the form of film element and securities thereof. SUBSTANCE: method is used for preparing document protected against counterfeiting by imparting to document visual information changeable from one document to other ; to this end document is provided with protection flag in the form of film element fixed to document through permanent joint so that document cannot be changed without its destruction and is passed through reader for reading changeable visual information disposed on film element before the latter is joined with document; visual information read out of film element is disposed on document beyond film element by means of reader-controlled printer. EFFECT: enhanced reliability, facilitated procedure of document protection against counterfeiting. 2 cl, 2 dwg
