How to prevent comments from duplicating on their own across multiple PDFs

Since it's happening across multiple PDFs and the comments increase without any input, you should check whether Acrobat is syncing the comments through Document Cloud. If possible, try opening one affected PDF while signed out of Acrobat or with syncing disabled and see if the duplicates still appear.

I'd also test the same file on another computer. If the duplicates only happen on that user's PC, it could point to a local Acrobat profile or cache issue rather than the PDFs themselves. I wouldn't keep removing the duplicate comments until the cause is identified.

Unfortunately, the person having the issue is out of the office - I will update once they return and I can get more information.

Hello @GJSchaller1972,

I hope you are doing well, and thanks for reaching out. We're sorry for the trouble you had.

Could you please share more details about the isuse:

1. Were these PDFs ever put through Share for review, Send for comments, or the Share button, and do they show up in Menu > View > Tracker?

2. Where are they stored, local disk, OneDrive, SharePoint, a network share, or a document management system?

3. Does the duplication still happen on a local copy opened offline?

4. Exact Acrobat version/build (Menu > Help > About), and Acrobat Pro or Reader?

Thanks for the clear description, and the key detail is the one you highlighted: the count climbs while the file just sits open, with no user action. That behaviour, across multiple files, is the classic signature of a comment-synchronisation loop rather than anything your user is doing wrong. In other words, these PDFs are almost certainly still tied to an Adobe shared review (Share for review / Send for comments), or they live in a synced storage location, and Acrobat's background comment sync keeps re-pulling the same comments on a timer. Acrobat re-checks for new comments roughly every 10 minutes while a review file is open and even after it is closed, which is exactly why the number keeps growing on its own. That also explains why switching UI modes did not help, this is a sync issue, not a UI one.

Suggestions:

Confirm it is sync. Copy one affected PDF to a local folder like C:\Temp, disconnect from the network or pause the cloud client, and open it there. If the count stops climbing, sync (a shared review and/or the storage sync client) is confirmed. Avoid opening these files directly from OneDrive/SharePoint/a network share while testing.

Check the Tracker and end the review. Open View > Tracker and look under Reviews (Sent or Joined) for these files. If they are listed, select the file and End Review (if your user joined someone else's review, remove themselves instead). That stops further synchronisation for that file.

Save a disconnected copy. With the file open, use File > Save As Archive Copy, which saves a copy that is no longer connected to the review, so the comments become ordinary embedded annotations that cannot re-sync. If that option is not present in your build, a plain File > Save As to a new local filename also breaks the association. Have the user work only from that clean copy going forward.

Turn off shared-review sync. Menu> Preferences > Reviewing, and deselect "Share For Review Using The Adobe Document Cloud." In an enterprise setup, IT can also disable shared reviews fleet-wide via the Acrobat Customization Wizard, which switches off the synchroniser.

For more details, you can also refer to these articles, and try the suggestions: https://adobe.ly/4xw7vT7

https://adobe.ly/4cCKOnB

I hpoe this helps, and please reach out if you experience any issues, or need any assistance.

Regards,

Anand Sri.