How to Add or Remove Watermarks and Signatures in PDF (Step-by-Step Guide)

Watermarks are essential for protecting intellectual property. These semi-transparent images can be the difference between your work being protected and it being stolen by a competitor. They are small logos that can be overlaid on digital content, such as photos, videos, and documents. Most commonly used by photographers, artists, and legal professionals, they identify ownership of PDFs (Portable Document Format) and safeguard against theft. 

Digital signatures are also just as important as watermarks, as they authenticate your online documents and verify the identity of the person who signed them off. 

What Are PDF Watermarks and Signatures?

Both watermarks and signatures are commonly used for branding digital documents. They both add a visible mark to online property. However, their purposes are slightly different. As a creator of digital content, it’s vital that you understand the differences between the two. 

What is a Watermark in a PDF?

A watermark is mainly added to a document for visual and informational purposes. A standard watermark is semi-transparent, meaning you can see some details of the digital product it overlays. Ideally, a watermark does not interfere with the readability of the document. 

Besides company logos, you may also see watermarks in the form of block capital letters reading ‘CONFIDENTIAL’ or ‘DRAFT’. In this case, the watermark is being used to indicate the current status of the document or signal to readers that it contains confidential information. This helps to prevent unauthorized sharing of the document. 

It’s worth noting here that watermarks can be easily removed using PDF tools. They are, therefore, not used to completely secure a document from theft, but rather visually imply that the document cannot be stolen or repurposed. 

What is a Signature in a PDF?

To put it simply, a signature is used to verify the identity of the person who made the PDF. A signature is added to the PDF to ‘sign off’ on the document, meaning that the work has not been edited since the time of signing. 

There are two main types of signatures you can apply to a PDF - digital signatures and handwritten electronic signatures. Digital signatures are encryption-based and link signers to documents. Typically created using Public Key Infrastructure (PKI), they ensure the integrity of the document and confirm that the PDF has not been altered since it was signed. 

Handwritten electronic signatures, on the other hand, serve as visual representations of a person’s signature. They are commonly drawn on a touch screen, but can also be typed or scanned. While they are easier to create than a digital signature, they are less secure and can more easily be forged. 

Method 1 – How to Add Watermark to PDF (Using Smallppt)

Adding a watermark to a PDF doesn’t need to be difficult. It can be easily done using an online tool, and normally only involves uploading a document, watermarking it, and then saving the new document. 

Why Use Smallppt

Out of all the online tools that you can use for watermarking a document, Smallppt emerges as one of the best options. It is simple, intuitive, and free to use (no installation is required). 

Plus, you can convert multiple file formats to PDF using the platform, including JPG and PNG. 

Simply select ‘AI PDF’ from the tab on the left-hand side of the Smallppt menu. 

Next, a menu of options will appear. On the right-hand side, click on the option that states ‘Watermark PDF’. 

At the top of the page that opens, you’ll see the option to ‘Select File’. Click on this and upload the file you’d like to watermark. 

Next, you can adjust the options to make the most suitable watermark for your document. Specifically, you can choose the watermark type (text or image), font size, and opacity (among many other options). 

Once you’re happy with all the options, click ‘Add Watermark’. Your PDF with the watermark added will then download automatically. 

Method 2 – How to Remove Watermark in PDF

There are also many free ways of how to remove watermark in PDF. For example, you could use a tool such as LightPDF to do the job. 

From the ‘PDF Tools’ drop-down menu, select PDF Watermark Remover’. 

Click on the ‘Select Files’ button that appears on the screen. Once you click on it, you’ll be able to upload the file you want the watermark removed from. 

Once you’ve selected the PDF, a document viewer will appear. On the right-hand side, select ‘Remove’. This will erase the watermark from your document. 

Method 3 – How to Add Signature to PDF

To add your signature to a document, choose one of the following options: 

Option 1: Add Signature with Smallppt

At the moment, Smallppt can only be used to add a text-based signature, rather than a digital version of your written signature. However, a future version of the tool will allow you to sign documents via a trackpad. 

Here’s how to add a text-based signature: 

As before, select ‘AI PDF’ from the menu on the left-hand side. Except this time, select ‘Add Stamp to PDF’. 

On the next page, select your PDF by clicking on the ‘Select File’ button. 

Fill out the rest of the form - select which page of the PDF you’d like the signature to be on, and define where it will appear on the page using the ‘Position’ option. 

Insert your signature in the ‘Stamp Text’ section. 

Once you’re satisfied with all the settings, click ‘Submit’ and the signature will be added to the PDF. 

Option 2: Using Built-in Tools 

You can also add a signature using built-in tools, such as Mac Preview. 

Open Mac Preview, select your PDF, and click ‘Open’. 

Click on the ‘Sign’ icon and, if you have a saved signature, select this from the drop-down menu that appears. 

If you don’t have a signature saved, click ‘Create Signature’. Here, you can create a signature using your trackpad. Alternatively, you can sign a piece of paper and photograph it using your Mac’s camera. 

Move the signature to the point in the PDF where it needs to go. Once you’re happy with it, select ‘save’. 

Method 4 – How to Remove Signature in PDF

You shouldn’t need to know how to remove signature in PDF. Once you sign it, it means that you’re happy with the documentation and that no further edits are to be made. 

Plus, most PDF editors ‘lock’ the work after you’ve signed it, meaning you can’t remove the signature. 

However, mistakes happen, and changes sometimes need to be made to the document. If you added the signature on Mac Preview, it is possible to remove the signature. 

Open the signed document in the Preview app. 

From the toolbar, select the Rectangular Selection box. 

The signature should be highlighted once you click on it. From this point, click the delete key on your keyboard. This should remove the signature. 

Tips for Managing PDF Watermarks & Signatures

In addition to adding watermarks and signatures to your PDFs, there are ways you can manage your documents to ensure they remain secure, compliant, and professional. 

Use transparent watermarks for better readability 

Transparent watermarks are industry standard. While watermarks should only take up a small part of the document, they can obscure vital information if you make them opaque or too big. Therefore, it’s important to make them somewhat transparent. 

Keep the opacity low enough to read the text positioned behind it. Additionally, you should also place the text diagonally and keep the text to a single word. For example, ‘CONFIDENTIAL’ is all you need to convey the message and watermark your work. 

Keep the original file backed up 

Another top tip is to always have a version of the file without the watermark. An unmodified version means that you can skip the removal of the watermark step, as you’ll always have a clean version ready.  

This is particularly important when it comes to signing PDFs. Once the document is signed, it signifies that the document is completed and unedited. Should you need to make modifications to this version of the document, the signature would become invalid. Therefore, having original files means that you can make revisions and create new versions of the document.

Overall, having un-watermarked versions of the document ready provides you with greater flexibility. 

Don’t lock the signature until it’s finalized 

Once you sign or watermark a PDF, it is possible to ‘lock’ the document. By locking it, you are effectively agreeing that the document is finalised and no further edits are to be made. Once locked, editing the document is prohibited. 

Therefore, it is essential that you review and approve all the information in the document before signing it off. This will allow you to forgo having to restart the document should any further edits be required after signing. 

Conclusion

Now you know both how to add watermark to PDF and how to remove watermark in PDF. To recap, it’s possible to add a watermark and a text-based signature to a PDF document using such tools as Smallppt. This platform offers fast and free PDF editing, allowing you to expertly add watermarks to your documents. 

Should you need to remove the watermark you added on Smallppt, you could use a tool like LightPDF, which can clean your page almost instantly. 

When it comes to how to add a signature to PDF, the best option would be using a built-in tool like Mac Preview. This platform not only allows you to add a signature to your document using the trackpad, but it also allows you to easily remove the signature should you need to.