Tulsa police are investigating a recent rash of check frauds where the person writing the checks, used disappearing ink.  The News On 6's crime reporter Lori Fullbright reports one business is making sure customers use the store's pen to write a check.

The Wonder Bread thrift store last week has a sign that reads, "You must fill out your checks with our ink pens."

Below that, it says, no out of state checks or driver's licenses, which are also a part of the scam.  Wonder Bread declined a request from The News On 6 for an interview, but Tulsa Police say the store has been a victim of a customer using disappearing ink to fill out checks.

"The consumer will actually write a check, you'll look at it, everything looks good, but they've used invisible ink, which means a couple of hours later, that ink has disappeared off the check and the business is left with a blank check and the merchandise has walked out the door," said Rick Brinkley with the Tulsa Better Business Bureau.

You can find disappearing ink pens for sale all over the web.  One even gives some options; the ink can disappear in a few hours, a few days, even a week.  They say it's for protection when you write highly personal letters or top secret business letters.

The concept is the same as this disappearing ink purchased at a magic shop.  You squirt it and it looks like you've made a mess, but the truth is, once the ink is exposed to the air, a chemical reaction happens and the ink evaporates, much like water.

All that is fine for practical jokes, but it's much more serious when someone is using the ink to commit felony fraud, which is what's happening.

One give-away is the ink often has a red or pink tint to it.

The only real protection against it is to do what the Wonder Bread store is doing.  That is make people use pens the store provides.

"They shouldn't be offended by it.  They've gotta realize the business is doing what it can to protect itself and at the same time, protect us from prices going up," said Rick Brinkley with the Tulsa Better Business Bureau.

One fraud detective says if stores require you to use their pen, they should offer you a gel pen instead of a regular ball point pen.  That prevents a store employee from later washing the check and removing your ink and committing fraud against you.

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