Two sensitivity labels on PDF file

HI courtney_green​ 
This might be related to how sensitivity labels are handled in PDFs versus Office files.

In Office documents (Word, Excel, PowerPoint):

• Only one sensitivity label can exist at a time
• Applying a new label replaces the old one
• You cannot have two active labels simultaneously

However, for PDF files, things are different.

Why two labels can appear on a PDF

This usually happens when:

1. A PDF is labeled in Microsoft Purview / Office
2. The same PDF is later labeled again using:
   • A different application (for example Adobe with the MIP/AIP plugin), or
   • A different labeling method (auto-labeling, DLP action, or a service-side process)

Some third-party PDF editors or older AIP/MIP integrations:

• Write label metadata in a different location inside the file
• Do not properly remove or overwrite the existing label metadata
• Result in two label entries being embedded in the PDF

Purview Activity Explorer will show both labeling events, which matches what you observed.

Why you cannot reproduce it with Office

When you apply a label to a Word file, convert it to PDF, and re-label it, Office handles this correctly and replaces the existing label, so you will only ever see one.

The dual-label scenario almost always involves:

• A PDF that was labeled more than once using different tools or labeling engines, or
• An older AIP client or PDF plugin

Why your PDF editor could remove them

Many PDF editors can strip or rewrite the metadata sections where labels are stored, which effectively removes one or both labels. Office does not expose this because Office files do not support multiple labels by design.

How to prevent it

To avoid this going forward:

• Standardize on one labeling method for PDFs (preferably built-in Purview labeling)
• Avoid mixing old AIP clients, Adobe MIP plugins, and multiple labeling tools
• Ensure all clients are updated to the latest Purview labeling client
• Review auto-labeling and DLP actions that may apply labels to PDFs

If you do end up testing this further, I would be very interested to hear the results and whether you are able to reproduce it in your environment. ✌️I hope that helps.