Why Detector Pens Will Not Save You From Counterfeit Money

Money counterfeiting, as any other crime, doesn't stand still. Fraudsters continually evolve their methods to circumvent new counterfeit detection methods, and businesses and law enforcement agencies must to do the same to stay a step ahead. The counterfeit detector pen serves as an excellent illustration of the never-ending battle between the two, and the dangers of falling behind in the race with counterfeiters.

The original DriMark detector pen was patented on a simple premise: look for the presence of starch, commonly used in commercial paper production to make the pages crisp and white. U.S. dollars are printed on cotton paper which doesn't react to iodine in the pen, while counterfeits circa the time of the pen's inception were printed over regular office paper. Mark a fake bill with the pen, the idea went, and the color turns from golden yellow to bluish black, exposing it.

Sure enough, it didn't take take long for counterfeiters to find a solution. Coating fake bills in a substance that iodine can't penetrate – as simple as hairspray – produced a barrier between starch and iodine, preventing the reaction. The ink remains the same color. Or even more simply (and this was reportedly noted by the police in Los Angeles), a fraudster could walk down the paper aisle of the local office supply store and mark every brand of paper with the detector pen until finding one that did not change color.

Despite this well-publicized criminal breakthrough, too many business owners continue to believe in the efficacy of the pens. A recent interview of a Marion County, IN pizzeria owner who got scammed out of $100 revealed the typical business attitude towards conterfeit detection: “Yes we now have one of those marking pens that stays gold if it's real and turns black if the bill is counterfeit" he said, adding that if he had it prior to the crime he could have saved himself from losing the money.

He couldn't be more wrong. In fact, a lot of modern counterfeits will easily pass the pen test. They only remain popular partly due to public ignorance of their ineffectiveness and partly to their attractive price. Business cheaping out on these pens as their only means of counterfeit detection, however, risk losing a lot more than the $100 the unfortunate pizzeria owner did.