This is an oft asked question by a lot of clients and relies on a basic 
misundertanding of how documents are passed around the internet.
Basically, it is impossible (see examples below). If you don't want 
information copied from your web page then don't put in on the web. period.

Additionally, copy+paste is one of the most fundamental actions on any device, 
disabling it is pretty rude and nigh on impossible anway - on some desktop 
environments you can determine your own keystrokes to copy and paste that are 
known only to you and can't be detected by client side code
e.g Ctrl-Alt-Tab-C for copying

1. "Lets disable right click functionaity!"
- users lose functionality
- easy workaround

workaround 1:
$ wget http://www.example.com/ > 'copy of your home page.html'
workaround 2:
install some firefox extension to ignore right click disable requests by a 
workaround 3:
use the google cache or the web archive
workaround 4:
take it out of the brower cache - where it is copied anyway

2. "Let's encrypt the html!"
no such thing - it's encoding, not encryption. When you encode something 
anyone can decode it.  If it is encryption you'd have to pass a shared key to 
a public resource or expect your visitors to have that encryption key.
slows down page rendering - it has to be decoded by JS usually.

workaround 1:
- decode_function(html) > 'decoded copy.html'

3. "Let's disable the printer requests!"
- see workaround 1.3,1.1,1.4

4. Use images / flash / pdf to render content
- content generally inaccessible to search engines and screen readers
- decode with OCR technology (crackers can easily do this with captchas)

5. transparent image over content
- adblock the image
workaround 1:
- save as > file.html > "html only"

Copyright infringment is best left up to the lawyers - but then there is the 
argument of content being in the public domain anyway.

If you are in a closed intranet environment one way to do it would be to 
employ someone who runs around everytime a page is rendered in a browser and 
shouts very loudly "remember not to copy and paste!" :)


On Fri, 21 Dec 2007 09:48:17 am Nick Roper wrote:
> Hi,
> We have been asked by a client whether it is possible to any extent to
> prevent/deter users from copying content from a particular web page.
> The page will comprise two main areas:
> 1) Selection options in the form of select lists, check boxes etc.
> 2) Once the criteria have been selected then a 'Search' button will
> initiate a script that will query the database and display resulting
> text records in tabular format.
> The requirement is that the the user should be able to view the
> resulting output, but not to be able to copy/paste to other applications.
> Is this possible to achieve in a way that is standards-compliant - or
> indeed in any way at all? One suggestion has been to apply a transparent
> image over the results table - but not sure if this could be done with
> CSS etc?
> If this is considered off-topic then I would welcome suggestions for
> more appropriate forums.
> Many thanks in anticipation.
> Regards,

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