Patent ID: 7314216

Claim:
A method of marking a unique code onto an edge of a sheet of material, comprising: providing N 1 stacks of sheet material, each stack having N 2 sheets of sheet material, where N 1 times a number N 2 =N; defining a unique first identification code for each of the N 1 stacks of sheet material; for each of the N 1 stacks, printing a first barcode corresponding to the each of the N 1 stack's unique first identification code on at least one edge of the stack so that each sheet of sheet material in the stack has the first barcode printed on its edge; collating the N 1 stacks of sheet material to form N 2 stacks, wherein each of the N 2 collated stacks has N 1 sheets of sheet material, one sheet from each of the N 1 stacks of sheet material; defining a unique second identification code for each of the N 2 stacks of sheet material; for each of the N 2 stacks, printing a second barcode corresponding to the each of the N 2 stack's unique identification code on at least one edge of the stack so that each sheet of sheet material in the stack has the second barcode printed on its edge; forming a single ream comprising the N 2 stacks; printing a third identification code on at least one edge of the ream so that each sheet of sheet material in the ream has the third identification code printed on its edge; and wherein each sheet of material in the ream has indicia arranged on a least one edge to form a code uniquely identifying the sheet of material.