Abstract: Supplementary coding on inductive debit cards and reading method by which information regarding variables, such as date of issue and country in which the card is valid, are included without any change in the number of credits on the card by using front and back handling strips normally provided on such cards. Such an encoding comprises the division of the strips, into a number of segments or tracks equal to the number of cell columns on the card, each track coinciding with the columns. Metalized tracks correspond to bit "1 " and non-metalized tracks to bit "0 ", the 4 tracks located at the corners of the card always being metalized. Reading of the information on the card is carried out during the insertion of the card into a reading head by a row of sensors farthest away from the entrance slot of the reading head. On detecting the presence of a pair of metalized tracks on the corners of the card, the bits contained in the handling strip are read and stored in a temporary register for later interpretation.

Abstract: An improved debiting method for inductive prepayment cards is provided in which a credit card cell set is divided into sectors for collection purposes, all credits collected from a given sector are collected before the next sector is collected from, the sectors are accessed in a standard order valid for all cards, each sector is made up of a column of cells parallel to a longitudinal axis of the card, and the credit cells are always accessed from the card's internal transverse edge toward the external transverse edge, independently of the orientation in which the card has been inserted in a read/write head.