If I give an RFID-enabled key fob to each shopper, can I then monitor that individual without notice?
You might be able to, if the transponder in the fob could be read at a reasonable distance—but it would be a very bad idea do so. First, some countries have outlawed such practices. And even in nations that do not forbid tracking consumers without their knowledge, it would be easy to detect an RF signal from a reader and identify the surreptitious tracking, so you would be exposed and your customers would likely be very unhappy. The bad press you’d receive would likely cost you a great deal of business—and frankly, I’m not sure there is much business benefit to tracking customers without their knowledge.
If you are trying to gather data regarding customer behavior, I would recommend offering an RFID loyalty key fob, letting your customers know what information you plan to collect, offering them discounts in exchange for their participation and allowing them to opt into or out of the program. Anything else would be unethical, and quite possibly illegal as well.
—Mark Roberti, Founder and Editor, RFID Journal
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