PDF SEcurity and Watermarks

How to Add Security to PDF Files with Watermarks

Did you know that watermarks applied with Adobe® Acrobat can be easily removed, even if the PDF file is password protected? For watermarks to be effective, they need to be applied in a way that any attempt to remove or alter them is evident. Otherwise, what is the good of applying watermarks at all?

ActivePDF wants to ensure that all your digital documents are safe from theft, unauthorized alteration, or any other misuse detrimental to the security of your or your clients’ sensitive data. This is why we're taking a deep dive into watermarks and providing the proper functions when applying them to your documents.

Why would someone watermark PDF files?

Watermarks have been used as a source of document security for centuries, originally implemented with traditional paper. In fact, the first watermark was introduced in Italy all the way back in 1282.

Today, thanks to digital transformation, watermarks are alive and well within digital documents. Let's explore why securing digital watermarks are imperative to the security of your documents, as well as a few operational functions you need to know when correctly adding, removing, and/or updating watermarks within a PDF file.

How do I add a watermark to a PDF file?

Before showing you how to add, remove, or alter a watermark in a PDF, let's take a moment to go over why watermarks are used in PDFs in the first place. As mentioned above, when correctly applied, watermarks are one of the more secure features used to protect digital documents.

Adding watermarks to a PDF as a security measure preserves your information while still enabling the file to be shared. Watermarks can be used as a simple reminder that a document is classified. In this usage, watermarks ensure that documents are categorized properly, and when labeled "confidential," the PDF file isn't accidentally put on a public facing link (or similar non-confidential use).

Watermarks can also be used to keep track of copies. You could add a unique watermark to each copy enabling you to easily track a leak back down to it's source. This proves to be a powerful deterrent against those who may otherwise leak confidential or private information to friends, family, or to the media.

Inserting a watermark on a PDF file for branding purposes has also become a common practice. In this instance, the watermark is simply used to add your logo to the top middle, top left, top right, bottom left, bottom middle, or bottom right of each page. This is a subtle way to keep your branding on all content – something that shouldn't be discounted, as people may find your PDF files on search engines and thus the watermark could be the first touch point for brand awareness.

What Software Will Add, Remove, or Modify PDF Watermarks?

There are many PDF watermarking options available, which is why the first step in adding, removing, or modifying watermarks in a PDF file is to choose the right software that will execute this for you properly.

Any tool that promises to edit your watermarks online should be avoided. This is because these tools typically are plagued by security and performance issues which could slow down your team and possibly result in compliance issues in the future.

Both security and performance issues actually boil down to the same cause – servers. An online converter (especially a free one) will store your file on their servers (this is a big security and compliance risk). The server will then work to add or remove a watermark. This operation will most likely be encumbered by a slow, underpowered server under heavy load resulting in a less-than-desirable wait time and output.

Instead, consider using a respected PDF manipulation tool that is built for developers which can be downloaded and run from your own server or workstation. The award-winning DocGenius™ Toolkit by ActivePDF is an industry-leading option, with simple and transparent pricing that opens up hundreds of methods and properties (including watermarking tools) for .NET PDF developers.

Get started with a Free Trial of Toolkit:

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How to Watermark a PDF File with Toolkit 


Step 1:

Download Toolkit by ActivePDF examples and DDLs from GitHub. Before running the example, be sure your computer meets the following system requirements:

*Not needed if installing Toolkit via installer. Since these steps include examples and pre-embedded on GitHub, evaluators will need to manually install the Visual C++. 

Note: If you are installing an ActivePDF product on a Windows 2012 server, you need to download and install two Microsoft updates for Windows 2012 servers. These updates resolve issues with the Microsoft Visual 2015 C++ Redistributable Runtime Components. For links and step-by-step instructions, see this ActivePDF Knowledge Base article: Installing Toolkit on Windows 2012 Servers.


Hardware Requirements

The minimum hardware requirements for Toolkit are: Server and Desktop

  • 125 MB of RAM
  • 50 MB of hard disk space (for application)

Step 2:

Extract .zip file and save extracted files to desired folder location.


Step 3:

Open the Toolkit solution “ActivePDF.ToolKit.Examples.CSharp.sln” with Visual Studio.

PDF watermark component, watermark samples, PDF watermarking examples


Step 4:

There are multiple Toolkit sample functionalities in the Program.cs file. The default uncommented sample demonstrates adding a watermark CONFIDENTIAL to the centered of the PDF file.

PDF API watermark, watermark samples, PDF watermarking examples

PDF watermark DLL, watermark samples, PDF watermarking examples


Step 5:

Execute the sample code. Open the output file “AddCenteredTestWatermark_Output.pdf” located in the OutputFiles folder in the main Toolkit sample project (C:\Toolkit_Examples_CSharp-master\ActivePDF.ToolKit.Examples.CSharp\OutputFiles). As you can see below, the grey watermark CONFIDENTIAL is now added to the center of the PDF page.

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PDF Watermark and PDF Security Summary

There you have a quick and easy course on how, why, and when to add, remove, and update watermarks within a PDF file. Now that you know the basics of watermarking, there's no reason to not use this powerful and secure feature within your PDF files.

Have more questions about watermarking, PDF technology, or digital transformation? Contact the knowledgeable technical advisors at ActivePDF today!

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Toolkit is the powerful developer tool that you need to create, modify, view, extract, and automate data to and from PDF files within software applications. The Toolkit library contains hundreds of properties and methods, designed to tackle any PDF-related task. Whether you need a few documents a day or thousands of pages a second, Toolkit is the high-performance PDF manipulation tool that helps get the job done!

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