# How does VOID on check when copied work? **URL:** \ **Category:** Factual Questions\ **Created:** [May 22, 2018, 1:09am UTC](https://boards.straightdope.com/t/how-does-void-on-check-when-copied-work/814597 "2018-05-22T01:09:40Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [May 22, 2018, 1:09am UTC](https://boards.straightdope.com/t/how-does-void-on-check-when-copied-work/814597/1 "2018-05-22T01:09:40Z")
First, I do not want to circumvent security features or do anything illegal. Do not try to tell me how to do that in this thread. I am just curious from an engineering standpoint. Many checks have what looks like a swirly random pattern on the face but if you try to photocopy or scan it, the copy will have the word VOID printed all over it. How do they do that? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [May 22, 2018, 1:39am UTC](https://boards.straightdope.com/t/how-does-void-on-check-when-copied-work/814597/2 "2018-05-22T01:39:24Z")
The dots are different sizes. The ones that spell “void” are just large enough to be resolved by a typical copier. The background dots are too small. So, when the check is copied, only the “void” shows up. Also, the dots may actually grow in size when copied, so the “void” becomes even more obvious. ---
**Author:** ![crowmanyclouds](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crowmanyclouds/32/19884_2.png) [@crowmanyclouds](https://boards.straightdope.com/u/crowmanyclouds)\ **Post date:** [May 22, 2018, 3:13am UTC](https://boards.straightdope.com/t/how-does-void-on-check-when-copied-work/814597/3 "2018-05-22T03:13:50Z")
The phrase you’re looking for is - [void pantograph](https://en.wikipedia.org/wiki/Void_pantograph). CMC fnord! ---
**Author:** ![TRC4941](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/trc4941/32/6792_2.png) [@TRC4941](https://boards.straightdope.com/u/TRC4941)\ **Post date:** [May 22, 2018, 2:53pm UTC](https://boards.straightdope.com/t/how-does-void-on-check-when-copied-work/814597/4 "2018-05-22T14:53:14Z")
Some business checks I receive have a small shiny silver square on the front. These always seem to be the ones that don’t have a stub attached so I need to take a copy of the check for my files. That silver square causes the copy to come out as just a solid black sheet of paper. I have to cover the square up so I can get a readable copy. ---
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [May 22, 2018, 2:58pm UTC](https://boards.straightdope.com/t/how-does-void-on-check-when-copied-work/814597/5 "2018-05-22T14:58:02Z")
> [@TRC4941](#): > > Some business checks I receive have a small shiny silver square on the front. These always seem to be the ones that don’t have a stub attached so I need to take a copy of the check for my files. That silver square causes the copy to come out as just a solid black sheet of paper. I have to cover the square up so I can get a readable copy. I have not seen that. I am guessing that the silver reflects so much light that the copier, in trying to get the correct average exposure for the whole sheet, underexposes it, rendering it black. ---
**Author:** ![mixdenny](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mixdenny/32/2962_2.png) [@mixdenny](https://boards.straightdope.com/u/mixdenny)\ **Post date:** [May 22, 2018, 4:02pm UTC](https://boards.straightdope.com/t/how-does-void-on-check-when-copied-work/814597/6 "2018-05-22T16:02:05Z")
When we pick up a new prescription script for hydrocodone it is written on paper with seven security features that are listed on the back. I spent some time trying out the ones I could. There were orange lettered warnings on the back. These turned yellow when rubbed or heated. They work great and return to orange after they cool. When you rub on the back with a coin lettering appears. Works great and exposes lines of confirmation that the paper is real. They are permanent. All across the back is a series of closely spaced diagonal lines of very faint gray that vary in width and do not reproduce. When you look at the back at a 45 degree angle a faint watermark appears. It is a function of those gray lines. On the front is the VOID that will appear if you try to copy. And two more VOIDs on the front, one appears from heat and the other from ‘chemical attack’. Dennis ---
**Author:** ![ftg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ftg/32/2801_2.png) [@ftg](https://boards.straightdope.com/u/ftg)\ **Post date:** [May 22, 2018, 8:48pm UTC](https://boards.straightdope.com/t/how-does-void-on-check-when-copied-work/814597/7 "2018-05-22T20:48:04Z")
So you use your smartphone to scan a check for deposit. The scan has “VOID” on it. The difference between this check and a copied, voided check is … ?