The EPC Gen2 standard dictates every bit in the EPC.  The EPC includes the following information: a header, the chip manufacturer, the chip model, our Company Prefix (CP) assigned to us by GS1, an Item Reference Number (IRN) for the vials and a Tag Identifier (TID). These numbers are then combined in a very specific way defined by the EPC Gen2 standard. The end result is a 96-bit EPC that is unique to every vial.