Patent ID: 8033450

Claim:
A method for automatically generating at least one expression code that is unique to a microparticle mark that includes a multiplicity of microparticles and is adapted to be scanned by an automated reader, the method comprising: determining whether each of the multiplicity of microparticles in the microparticle mark presents a valid microparticle by examining at least two different indicia expressed by the microparticle and comparing the at least two different indicia to predetermined indicia associated with the microparticle being a valid microparticle, the at least two different indicia representing information other than a location of the microparticle that are adapted to be determined by the automated reader; generating at least one signature string representative of at least one feature relationship among only the valid microparticles of the multiplicity of microparticles in the microparticle mark, the at least one feature relationship adapted to be determined by the automated reader; using a processing system to generate at least one expression code for the microparticle mark based on the at least one signature string and store the expression code in a storage system, the at least one expression code being unique for the microparticle mark; and accessing the storage system to utilize the at least one expression code to verify an authentication of a microparticle mark as scanned by the automated reader such that a tangible indication of the authentication of the microparticle mark is generated.