How to technically prevent copying or printing of copyright materials from a web page

[henry989]

Hello folks, I am new to this forum and in my first thread here I am asking for information on an important issue that I have been researching. My research brings me to this forum because I found a thread here with some discussion of the problem of how to technically prevent someone from right clicking to "stop them from copying and pasting text." More specifically I am trying to solve the following problem: Suppose one wants to post copyright material on the web so that people can see or read it on a web page, but NOT copy or print it because you want them to buy it, for example, as in an e-book; How can one technically prevent people from copying or printing this copyright material that they view or read on a web page? I think I have seen this on Google Books and other web sites that allow you to browse substantial portions of entire books but do not technically permit the function of copying or printing what you see on the web page. How is this done? Thanks, for any help.

Edit:

For reference, this thread is a re-hash of http://www.sitepoint.com/forums/show...ing-my-website
Mittineague

[dklynn]

Mitt,

You didn't close this thread because of the duplication?

989,

You simply can't enforce non-copying if you display it on your website. If nothing else, a print screen can capture the display which can be run past an OCR engine, etc. If you want to encode your information, you can password protect a page/directory or provide a one-time session to access the protected data. Please note that even encrypted PDF files can now be pretty easily hacked with apps that aren't very expensive at all.

Regards,

DK

[sahostking]

AS stated by dkylnn it is quite easy now adays

I would follow these steps.

Password protect a directory
Use .htaccess file to allow access to the directory via certain IPs only.
Ensure PDFs are only downloadable via logins
Definitely use sessions on your site

[GilDawson]

A possible example site that may have sufficient copy-blocking is snopes.com. You cannot simply select the text of a snopes report by dragging. You can, of course, get at the underlying html -- and thus the text itself -- by a number of methods. As there are both "Print this" and "Email this" buttons on the page, however, the casual visitor thwarted in a simple copy operation will likely take one of these routes to obtain a copy, thereby providing the snopes folks some information on the way.

So, how do they do this?

I trust I am not revealing any trade secrets by reporting that, in the View Source of a typical snopes report is a JavaScript function which seems to do the job:

<SCRIPT language="JavaScript">
if (window!=top){top.location.href=location.href;}
</script>
 
<script type="text/javascript">
<!--
var omitformtags=["input", "textarea", "select"]
omitformtags=omitformtags.join("|")
function disableselect(e){
if (omitformtags.indexOf(e.target.tagName.toLowerCase())==-1)
return false
}
function reEnable(){
return true
}
if (typeof document.onselectstart!="undefined")
document.onselectstart=new Function ("return false")
else{
document.onmousedown=disableselect
document.onmouseup=reEnable
}
-->
</script>

Clever, eh?

--Gil

[dklynn]

... and turning off JavaScript didn't work to enable click-and-drag? Too easy, IMHO, to circumvent the simple guards out there.

... and you can easily get around any of these guards (including invisible <DIV> over the image/text)) by simply taking a Print Screen capture and dealing with the image/text in a photo editing program (especially easy with OCR for the text).

Even PDF security can now be broken by inexpensive programs which can hack the Acrobat's security.

The bottom line is in my original response: If you make it available, you can't protect it.

Regards,

DK