# Not So Secret Secrets **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [April 18, 2008, 4:01am UTC](https://boards.straightdope.com/t/not-so-secret-secrets/445842 "2008-04-18T04:01:01Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![IdFindAnAAnswerForThat](https://avatars.discourse-cdn.com/v4/letter/i/3d9bf3/32.png) [@IdFindAnAAnswerForThat](https://boards.straightdope.com/u/IdFindAnAAnswerForThat)\ **Post date:** [April 18, 2008, 4:01am UTC](https://boards.straightdope.com/t/not-so-secret-secrets/445842/1 "2008-04-18T04:01:01Z")
I overheard our copier guy at work today saying that the copies we make have small bits of yellow ink too small to be seen normally, that idenify the copier that made it. I find this hard to believe but I can see how it would be possible. I was just wondering what other things you’ve heard about that are “so called secrets” like the above, but everyone knows about. Whether or not they are true I guess is a different thread, but I just kind of wanted to get a list. ---
**Author:** ![Santo\_Rugger](https://avatars.discourse-cdn.com/v4/letter/s/e95f7d/32.png) [@Santo\_Rugger](https://boards.straightdope.com/u/Santo_Rugger)\ **Post date:** [April 18, 2008, 5:37am UTC](https://boards.straightdope.com/t/not-so-secret-secrets/445842/2 "2008-04-18T05:37:15Z")
Here’s a site that describes it: [http://w2.eff.org/Privacy/printers/docucolor/](http://w2.eff.org/Privacy/printers/docucolor/) Xerox machines capable of reproducing authentic looking currency are designed to to print images that look like money: [http://www.xeroxtechnology.com/acd](http://www.xeroxtechnology.com/acd) They’ve also patented a way to identify copies of regular documents: [http://www.xerox.com/go/xrx/template/inv\_rel\_newsroom.jsp?app=Newsroom&ed\_name=NR\_2007May30\_XeroxInnovation\_FluorescentWriting&format=article&view=newsrelease&Xcntry=USA&Xlang=en\_US](http://www.xerox.com/go/xrx/template/inv_rel_newsroom.jsp?app=Newsroom&ed_name=NR_2007May30_XeroxInnovation_FluorescentWriting&format=article&view=newsrelease&Xcntry=USA&Xlang=en_US) But, to answer the OP, you may be surprised they do it for movies, too: > **[Coded anti-piracy](https://en.wikipedia.org/wiki/Coded_Anti-Piracy)** > > Coded anti-piracy (CAP) is an anti-copyright infringement technology which marks each film print of a motion picture with a distinguishing pattern of dots, used as a forensic identifier to identify the source of illegal copies. > They are not to be confused with cue marks, which are black or white circles usually in the upper right-hand corner of the frame. A cue mark is used to signal the projectionist that a particular reel of a film is ending, as most films come to theaters on several reels o... ---
**Author:** ![jharvey963](https://avatars.discourse-cdn.com/v4/letter/j/54ee81/32.png) [@jharvey963](https://boards.straightdope.com/u/jharvey963)\ **Post date:** [April 18, 2008, 10:55pm UTC](https://boards.straightdope.com/t/not-so-secret-secrets/445842/3 "2008-04-18T22:55:33Z")
This one’s a little dated, but there was a “not so secret secret” regarding Tonopah, Nevada some years ago. My cousin worked in Tonopah for a while on this “secret” project and couldn’t talk about it, even though everyone pretty much knew that what was being built there was the … first Stealth aircraft. (Was it the fighter or the bomber? I’m not sure.) J. ---
**Author:** ![coffinjumper](https://avatars.discourse-cdn.com/v4/letter/c/8baadc/32.png) [@coffinjumper](https://boards.straightdope.com/u/coffinjumper)\ **Post date:** [April 18, 2008, 11:01pm UTC](https://boards.straightdope.com/t/not-so-secret-secrets/445842/4 "2008-04-18T23:01:20Z")
[Cockeyed.com](http://Cockeyed.com) offers you proof of this: [http://www.cockeyed.com/citizen/printer\_yellow\_dots/dots.shtml](http://www.cockeyed.com/citizen/printer_yellow_dots/dots.shtml) Can’t think of anymore of the top of my head, but i just know this’ll be one of those threads where we read it and think “that was a secret? hmmm”