A method and system for authenticating goods and thereby detecting and
deterring counterfeits are disclosed. According to one aspect of the
invention, a client utilizes data received from a host to generate a
plurality of security codes and to direct a printing device to print the
plurality of security codes on a plurality of products, without retaining
the plurality of security codes after the printing device has printed the
plurality of security codes on the plurality of products. After the
security codes have been printed, a person can communicate the security
code to the host, which can verify its authenticity.