Most of the basic protection features are applied by default stop PDF copying, editing, screenshots, etc. All of these security restrictions enable you to stop PDF files from being shared with unauthorized users, and control how they are used and how long they are used by authorized users. A list of these PDF restrictions are provided below.
Safeguard does not use passwords to protect PDF files since they can be easily shared or removed. Instead PDF files are protected using individual encryption keys that are securely and transparently relayed to authorized devices from a web server and stored encrypted in a keystore on the local device. The keystore is locked to individual devices so it cannot be copied and moved elsewhere. This can either be installed on a device Windows, Mac, iOS, Android , run from a USB stick completely offline zero installation solution , or accessed via a web browser zero installation.
When a user opens a protected PDF document the Viewer checks to see if the decryption key is available. If it is not present then the Viewer checks with the administration server to see if the user is authorized to view the protected PDF. If they are, the decryption key is transparently relayed to the client and the protected document opens.
DRM controls are enforced by the Viewer software. Safeguard protects PDF files from printing — it disables printing of PDF documents by default so you do not have to apply any additional controls to stop a PDF being printed. As well as using Safeguard to stop PDF printing for specific or all documents, you can stop printing on a user basis — you can disable PDF printing for some users but allow printing for others using the same protected document you only have to protect the document once for all users rather than on an individual basis.
Documents can be protected with zero prints available to stop PDF being printed and then individual users can be granted print rights by altering the number of prints available. If you allow printing, you can limit the number of times a PDF can be printed by each user in order to stop users distributing high quality copies of documents to others.
Document watermarking is recommended if you allow printing to discourage photocopies being made — see PDF watermarking below. The important issue is not whether you can stop a PDF being copied but whether the recipient of the copied file can use it. If you encrypt a PDF with a password you can give a copy of the PDF to another user along with the password and they can use the file. So the protection provided is worthless as a useful copy was made that could be used with others. Safeguard effectively stops PDF copying because a copy of the protected file is of no use to another user without the decryption key to open it.
Decryption keys are stored encrypted in a keystore which is locked to the device it was registered on — so only authorized users can open protected PDF files. Authorized users must be prevented from saving the PDF in unprotected format so no editing or saving options should be made available and unprotected files should never be stored on disk in temporary files where they could be easily recovered. For additional security the PDF Reader should prevent screen grabbing, and document owners should disable printing so photocopies cannot be made of printed documents.
If you are going to stop document sharing and editing then you have to stop Save As from being used so PDF documents cannot be saved in unprotected formats. The simplest way to do this is to not have the facility available to begin with. Some products use JavaScript to disable the Save As menu item or short-keys, but JavaScript can be easily removed or turned off in a browser environment and so cannot be used securely.
The only documents that can be copied are protected PDF files and they are useless to unauthorized recipients as they need the correct decryption keys to open them. You might want to think again. The way every browser works is by caching information to disk. And browser environments are possibly the least secure of all because if no software is installed on a device then you have no control over the actual environment so stopping screen grabbing and printing to file drivers is not possible.
See Secure Downloads for additional information on stopping downloads and copying. To stop the browser caching the PDF on the users system, they convert your PDF files to images when you upload them — so the document is no longer a PDF file but consists of just raster images. However, this provides a poor user experience since images are slow to display and print, and features such as search, bookmarks, and annotations are unlikely to be available. However, if you encrypt a PDF file and the user does not have the decryption key to use it then it does not matter if they can download it.
And if you apply DRM and licensing controls then authorized users those given access will be restricted as to what they can do with downloadable PDF files for example not being able to share them with others. Many cloud based systems claim to stop PDF forwarding — however users can share their login credentials with others so they have access to your documents anyway.
If a system uses document links then there is nothing stopping an authorized user emailing those links to other users along with the login information. Some systems state that they lock PDF files to email addresses or domains but that just means that you have to login using that email address or any email address that belongs to the domain. It does not stop PDF forwarding since authorized users can still give their login credentials to others.
That is also true of 2FA codes which provide little extra protection. A Safeguard protected PDF file can be forwarded and emailed to another user but the recipient will NOT be able to view it unless the document owner has authorized them to use it.
If you are the document publisher, you can email protected PDF files to users knowing that if they fall into the wrong hands they cannot be opened. However, there are occasions where you want to know how to lock a PDF so it cannot be edited, i.
To summarize, this process first takes the PDF and renders it into an image file - which prevents not only editing, but also protects the PDF from copying. The second step transforms it back to PDF format. If you want to switch it back to PDF after making your edits, you can simply go back and use the same tool again. Permission passwords created by our Protect tool are heavily encrypted, which would restrict viewing to those that do not have access to the password you choose.
Both of the tools to protect PDFs are free to use, and are accessible online, and through our desktop and mobile apps, for you to use anywhere, anytime. However, a way around this would be to merge your PDF into one unified document before going through the steps above. Smallpdf is the most popular online PDF software, and we currently cater to over 30 million monthly users, including a count of , businesses.
Regardless of your job title, or if you have a job at all, our aim is and will always be : to make PDF easy. Whether you need to lock a PDF from editing, merge, split, or even sign it with an electronic signature, Smallpdf allows you to do all of this through a simple drag-and-drop interface. As we attract users from every corner of the world, we also have the site translated into 24 different languages. The language setting is available at the bottom right-hand corner of every page.
Smallpdf guarantees that your files are encrypted with SSL encryption in our protected environment while you upload, convert, and download them.
These files are also removed from our AWS servers after 60 minutes. Learn more. Asked 10 years, 9 months ago. Active 1 year, 2 months ago. Viewed k times. I am thinking about converting those PDF files to Flash. Any other ideas? JJJ 32k 20 20 gold badges 86 86 silver badges 99 99 bronze badges.
Costa Costa 3, 11 11 gold badges 43 43 silver badges 77 77 bronze badges. You do know that anything you display to the user can be printed in some fashion or another If you serve it, they can find some way to use it.
You can't stop a user from printing the screen. If you have information you want to display and you don't want it being printed physically, PDF isn't exactly the format of choice. It's whole purpose is to be lovingly printed. In my business, the need for the PDF to not be downloaded is due to not wanting customers to be able to easily share downloaded materials with other people.
I make worksheets, and if they are easy to share, the customer is more likely to email them to a friend. If sharing them is made more complicated, they are less likely to want to go to the trouble.
Not being able to download them without having advanced computer knowledge is good enough for me. Hope this sheds light on a need in the industry. Things like being able to get a screen shot, etc. Hope this helps. I i — Janet Giel-Romo. Add a comment. Active Oldest Votes. Legionar 7, 2 2 gold badges 36 36 silver badges 66 66 bronze badges.
Browsers' developer tools make it trivial to get at anything sent to the user, and you're not going to stop screen capture programs. Heck, the user could use their mobile phone to take pictures of the computer screen… — Donal Fellows.
Right-click, view page source, get link of image under the transparent image. It's been in Firefox for as long as I can remember. I think I remember it existing in Mozilla Suite back before it got pared down into Firebird, which then became Firefox. I consider that under 'one of the ways of getting at it that requires digging into the source.
I say you can lock it down 'hard' but not 'make it secure. Ultimately you will need to: Create Images for each page Present those to the user on the web via your own interface html, flash etc Keep in mind flash wont work on Apple devices if that's required.
Claudio Nastasi Junior 9 9 bronze badges. Mark Redman Mark Redman 23k 19 19 gold badges 88 88 silver badges bronze badges. I believe Chrome has currently removed support for all plugins but Flash and applied a whitelist for which sites are allowed to run Flash I can download this file - it give download and also print options like normal pdf — obaid.
Jonathan Thurft Jonathan Thurft 3, 7 7 gold badges 43 43 silver badges 73 73 bronze badges. If you encrypt the PDF you can control how printable and changeable it is. You haven't mentioned what you're using to build the PDFs so the details are up to you. You might be able to do the same thing with layers Optional Content Groups as well, not sure.
Mark Storer Mark Storer These permissions are ignored by browser-based PDF viewers. Always happy to point out the obvious :.
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