Ladies and gen­tle­men: the ideas you are about to read are true. Only the pre­sen­ta­tion has been changed to make me look like less of an idiot.

Groupon is great. I love it. I’m addicted. Each day they “fea­ture some­thing cool to do at an unbeat­able price” and when enough peo­ple buy-in the deal is “on” (see: woot.com). There are thou­sands of restau­rants in Chicago, and I can’t get out to all of them. But when I see that I can get dou­ble the value for half the price, I am imme­di­ately tempted (read: brain­washed) into buy­ing the Groupon of the day.

How Groupon Is Sup­posed To Work

The sys­tem is sup­posed to serve cus­tomers who see unbe­liev­able offers to local busi­nesses. I buy a coupon; I either print it or present it on my smart­phone; and I usu­ally have an enjoy­able expe­ri­ence. The expe­ri­ence is almost as great as the busi­ness model.

Groupon’s Prob­lem

Most busi­nesses are still 10 years behind when it comes to inter­act­ing with cus­tomers. They want you to print a copy of every­thing. If you use Groupon’s iPhone app (sav­ing you, the cus­tomer, from print­ing a mean­ing­less piece of paper), Groupon’s client just jots down what­ever num­ber you show them on the screen.

PROBLEM:When you use their iPhone app, Groupon expects you to “Mark As Used”.

Expects” is where the vul­ner­a­bil­ity lies. The Groupon sys­tem never marks it used. They rely on the hon­est user. I’ve flashed my iPhone at a crowded lunch spot and had some­one from high school come up from behind and sur­prise me so I hur­riedly locked my phone and shoved it in my pocket.

The next time I vis­ited the same estab­lish­ment (as I had mul­ti­ple Groupons), I real­ized that the coupon I didn’t “Mark As Used” last time was still valid. An hon­est mis­take that exploits the hon­esty system.

Another sit­u­a­tion arose while I was out try­ing to use a Groupon on my iPhone where the man­ager had me email him a screen­shot of the num­ber. I mistyped his email address; he said he never got it; and had me write it down on the receipt. It was never claimed.

How To Cheat Groupon

Dis­claimer: You’re not really cheat­ing Groupon. You are cheat­ing the small busi­nesses who place their faith in the great Groupon community. I’m sorry Groupon, but if you didn’t think of this you should hire me or some­one with half a brain regard­ing security.

I am not respon­si­ble if you use these for per­sonal gain. Please don’t!

Pho­to­shop the print­outs by chang­ing one digit. Save as PDF, open in Pho­to­shop or Gimp, erase what­ever digit you want, and put another digit in there after match­ing the font. The restau­rant or bar won’t run the num­ber until you are long gone. Sleezy? Yes. Guar­an­teed to work? Yes.

iPhone app user? Take a screen­shot of your Groupon code, edit just like I pre­vi­ously men­tioned, bring up saved image/pdf/html to server or cashier. Same prin­ci­ple, less paper. The cashier will jot down what­ever num­ber you show them and charge you the difference.

Until Groupon fixes this loop­hole, you will be able to reuse and dupli­cate coupons end­lessly (or until the Groupon expires). I’m sorry to all the small busi­ness who will lose money because of this post. I really am. There’s always one guy in the crowd that has to ruin it for the rest of us. Sorry to be that guy.

Groupon, please fix this! I’ll post a fol­low up with some of my ideas.