In this update to my prior post "I Am Not a Number" we will review the wiping of a drivers license magstripe to maintain your privacy. As I mentioned before, the practice of running licenses through card-readers at restaurants/bars/other should always be objected to strenuously, but the removal of magstripe info provides additional protection should the situation warrant it.

Supplies for my experiement:
Magstripe Card Reader from eBay (about $50)
Cheap Rare Earth Neodymium Magnets from Amazing Magnets ($4, or free with purchase)
My Driver's License

The experiment proceeded as follows: Did a test read of my license. Got a string of readable data including name, DL#, Address, etc. Took the largest of the magnet assortment (D125D 1/2" Dia x 1/8") and rubbed the magnet perpendicularly along the magstripe twice. I did this away from my computer. Did another test read of the license — no data. The reader would not read the license.

And that was it! Having read a lot of data on the web saying that high coercivity stripes were hard to wipe, I thought I'd need to buy a larger set of magnets, but it wasn't necessary. As you can see, the magnet used was very small (but these magnets are admittedly very strong).

That got me to thinking about the magnets we have hanging around the house. So, I asked a friend if I could wipe his license with one of the magnets we have on the fridge. These are the little button magnets that are commonly found on the back of LED pins and for other cute uses. So, I ran his license through the reader and verified his data. Then, as before, I rubbed the magnets crosswise across the stripe twice and ran it through again — wiped — no data.

So it looks like I didn't need to buy the Rare Earth magnets after all and could have used the little magnets on our fridge. Oh well — all in the cause of privacy science.

A few days later I wound up in my least-favorite big-box store returning some gifts. Since I didn't have a receipt, the associate asked me for my license. I provided. He swiped. Confused expression. Swiped again. Confused expression. Swiped again, slowly. Finally, he typed in my zip code and gave the refund. Such joy, such delight in keeping my data mine!





Speak your mind

4 Comments so far

  1. Bill aka NO DooDahs! on December 31, 2007 11:48 am

    There's a good possibility that the first time a jack-booted thug, er, law enforcement officer, er, wait, "policeman," scans your card and finds it blank - … he may suspect a fraudulent identity card… and take you down to the station. Just a thought.

  2. James Wisdom on December 31, 2007 1:28 pm

    Bill, I think this is unlikely as my state has barcodes on the back of the license that carry the same information. Also can be verified thru the DL#. Last, I am an upstanding citizen who rarely interacts with police — and when I do it is only to compliment them on their upstanding service in the community or to ask directions.

  3. Magnetschmuck on March 8, 2009 2:08 pm

    One of the many things that magnet can do. But then, I don't have the guts to do it. It might come out differently for me.

  4. Anonymous on March 4, 2010 9:36 pm

    I was pulled over to be notified that my license plate light was out, something I would have no way of knowing unless I got out of my car every time I started it just to “be sure”. He made sure I had my insurance and took my license briefly..and came back a moment later to remind me to change the bulb.

    According to ‘James Wisdom’… this makes me “no longer an upstanding citizen” because I “interacted with the law”.

    I am a perpetual returner of things to retail stores… I have never in my life been asked for my license for anything other than proof of visual identity. If I have no receipt, it’s always been “store credit or nothing” as a policy weather I bought with cash or credit.

    I am curious to know what info my driver’s license could provide them in relation to something I bought with a credit card? I honestly have never heard of this here in Illinois, though occasionally places like best buy ask for a zip code when checking out.


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