Abstract: Counterfeit objects, such as products or documents, can be detected by checking associated ID numbers, which include one or more appended fields of one or more randomly selected digits, in a database containing the correct authorized ID numbers. This use of random selection makes it impossible for counterfeiters to effectively predict or anticipate correct ID numbers. For example, by using bar coded ID numbers with two distinct appended fields of randomly selected numbers, instead of traditional serial numbers, counterfeit products can be conveniently and positively detected either on a wholesaler's or vendor's shelf using a truncated outside ID number found on the product's packaging, or, for example, upon receipt of a customer's product registration card on which the complete inside ID number is found, this complete inside ID number having been concealed from casual perusal during the product's distribution.

Abstract: Coding systems utilizing machine-readable coding are disclosed. The coding systems are extremely simple to use and preferred embodiments of the machine-readable coding require no external reference or reference code or starting point or orientation for reading or decoding. The number of usable codes for any given number of code elements (bits or digits) is maximized, or, conversely, a minimum number of code elements is required for a given application, thus allowing each code element to be of maximum size for a given coding area. Also, methods and apparatus for encoding objects, and for reading, decoding, processing and using the information obtained from such encoded objects are disclosed. The coding may be applied to objects such as casino chips, currency, automated production line components, consumer products, household items, zip coded objects, etc.

Abstract: Registers are inclined to react to any interference as follows: if any one stage inverts, the entire register inverts. In one embodiment, one additional bit is associated with the register, which bit is used to indicate that interference has occurred. Registers may then be inverted to their original form or may, by equating the meaning of the inverted form of the information contents of registers to the original form, ignore disturbance(s) caused by interference. Information media such as magnetic or optical discs for storage of such information thereon are also disclosed. The invention brings order to information failures caused by interference and thus is able to use such failures as opposed to other approaches which fight such failures. The invention avoids the need to keep track of original and inverted forms of information, independent of interference.