Shadow of a hacker accessing metadata in a computer monitor

PDF Metadata: Find, Change and Remove Hidden PDF Data

PDF metadata is data about a PDF. 

Applications automatically add metadata to PDF files using information the user provides such as their name – as well as data gathered in the process of creating and saving documents.

PDF creators can also add metadata to their documents manually. They might add keywords to make their PDF files easier to catalog, index and search; to comply with accessibility standards; or to optimize them for search engines.

How to Find Metadata in PDF Files

1. Open any PDF file in PDFpen and click the Inspector icon on the top right corner of the toolbar. You can also access the Inspector by choosing Window > Inspector or using the keyboard shortcut ⌘-Option-I.

Screenshot of Tool Bar. Click Inspector to find PDF metadata.

2. A dialogue box will appear. Choose the Document Information tab. The information you see is the most easily accessible PDF metadata. 

Here’s what it looks like:

PDF metadata screenshot

How to Edit PDF Metadata

To add or edit PDF metadata, open the Inspector and choose Document Information. 

You can manually enter or edit these fields: Title, Author, Subject and Keywords.

You can’t edit the Created, Modified, File Size, Page Count, Page Size, Application and Producer fields, which are automatically generated.

Hidden PDF Metadata

There’s also metadata you can’t easily see, also known as third-party metadata. 

In PDF files, this might include the name of the program used to convert the file to PDF format and the metadata creation date. In JPEG files, it might include thumbnails.

Finding this hidden data requires some knowledge of computing, but it isn’t very hard to do. Someone who is computer-savvy could use a program such as Unix strings – see this Wikipedia article on strings (Unix) for more info – to dig for information.

Removing Third-Party Metadata from PDFs

PDFpen enables you to remove third-party metadata from PDF files with just a few clicks. Here’s how:

  1. Open the PDF file.
  2. Choose File > Create Optimized PDF. The Optimize Images dialog box below will appear.
  3. Check the “Remove third-party metadata” box at the bottom. 
  4. Click Create to create an optimized copy of your original PDF with no third-party metadata.
Screenshot of Optimize images dialog box, which includes the option of removing PDF metadata.

Why Remove Third-Party Metadata from PDF Files

Third-party metadata contained in PDF documents can reveal potentially sensitive information about you, your clients and the organization you work for. 

To avoid exposing details that could impair confidentiality, it’s important to remove both visible and hidden sensitive information from PDF documents, especially if you’re a legal professional. For more information, see Why You Need to Remove Metadata From Your Court Filings.

As an added bonus, third-party data removal also reduces PDF file sizes.

PDF Metadata Removal Brings Added Security

As of version 12, PDFpen enables third-party metadata removal. Combined with redaction and password protection, the ability to remove third-party metadata make PDFpen an even more effective tool for securing PDF files.

To learn about other useful PDFpen features for legal professionals, check out The Best PDF Software for Lawyers: Why PDFpen Might be it. For PDF security tips, check out How to Secure a PDF Document Using PDFpen.