We have found three tags that have two Electronic Product Codes. Why would this happen?
I assume you mean that you purchased the tags pre-encoded, and that the three tags each had two Electronic Product Codes (EPCs). It would not be possible for me to determine exactly what caused this, but there is only one field for the EPC. It is likely that somehow, someone wrote EPCs to user memory. When the tags were interrogated, both EPCs were read. I hope this answers your question, and I look forward to seeing you at RFID Journal LIVE! in May.
—Mark Roberti, Founder and Editor, RFID Journal
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