Abstract: A method of detecting false data recording media and a data recording media therefor useful in the cash-free procurement of products or service from automatic service rendering or product vending machines. For each data recording medium, the number of uses thereof is encoded on the data recording medium itself and memorized by each automatic service machine. A data recording medium is deemed correct by the automatic service machine if the number of uses encoded on the medium itself is not lower than the number of uses previously memorized in the automatic service machine; otherwise, the medium will be deemed false and can be withheld or otherwise rejected by the machine. Dissemination of information relative to a false data recording medium is achieved on presentation of the medium by encoding in addition to the aforesaid data, the number of uses of a data recording medium previously presented to the machine.